Team:UCL/codemirror/js

// CodeMirror, copyright (c) by Marijn Haverbeke and others // Distributed under an MIT license: http://codemirror.net/LICENSE

// This is CodeMirror (http://codemirror.net), a code editor // implemented in JavaScript on top of the browser's DOM. // // You can find some technical background for some of the code below // at http://marijnhaverbeke.nl/blog/#cm-internals .

(function(mod) {

 if (typeof exports == "object" && typeof module == "object") // CommonJS
   module.exports = mod();
 else if (typeof define == "function" && define.amd) // AMD
   return define([], mod);
 else // Plain browser env
   this.CodeMirror = mod();

})(function() {

 "use strict";
 // BROWSER SNIFFING
 // Kludges for bugs and behavior differences that can't be feature
 // detected are enabled based on userAgent etc sniffing.
 var gecko = /gecko\/\d/i.test(navigator.userAgent);
 var ie_upto10 = /MSIE \d/.test(navigator.userAgent);
 var ie_11up = /Trident\/(?:[7-9]|\d{2,})\..*rv:(\d+)/.exec(navigator.userAgent);
 var ie = ie_upto10 || ie_11up;
 var ie_version = ie && (ie_upto10 ? document.documentMode || 6 : ie_11up[1]);
 var webkit = /WebKit\//.test(navigator.userAgent);
 var qtwebkit = webkit && /Qt\/\d+\.\d+/.test(navigator.userAgent);
 var chrome = /Chrome\//.test(navigator.userAgent);
 var presto = /Opera\//.test(navigator.userAgent);
 var safari = /Apple Computer/.test(navigator.vendor);
 var mac_geMountainLion = /Mac OS X 1\d\D([8-9]|\d\d)\D/.test(navigator.userAgent);
 var phantom = /PhantomJS/.test(navigator.userAgent);
 var ios = /AppleWebKit/.test(navigator.userAgent) && /Mobile\/\w+/.test(navigator.userAgent);
 // This is woefully incomplete. Suggestions for alternative methods welcome.
 var mobile = ios || /Android|webOS|BlackBerry|Opera Mini|Opera Mobi|IEMobile/i.test(navigator.userAgent);
 var mac = ios || /Mac/.test(navigator.platform);
 var windows = /win/i.test(navigator.platform);
 var presto_version = presto && navigator.userAgent.match(/Version\/(\d*\.\d*)/);
 if (presto_version) presto_version = Number(presto_version[1]);
 if (presto_version && presto_version >= 15) { presto = false; webkit = true; }
 // Some browsers use the wrong event properties to signal cmd/ctrl on OS X
 var flipCtrlCmd = mac && (qtwebkit || presto && (presto_version == null || presto_version < 12.11));
 var captureRightClick = gecko || (ie && ie_version >= 9);
 // Optimize some code when these features are not used.
 var sawReadOnlySpans = false, sawCollapsedSpans = false;
 // EDITOR CONSTRUCTOR
 // A CodeMirror instance represents an editor. This is the object
 // that user code is usually dealing with.
 function CodeMirror(place, options) {
   if (!(this instanceof CodeMirror)) return new CodeMirror(place, options);
   this.options = options = options ? copyObj(options) : {};
   // Determine effective options based on given values and defaults.
   copyObj(defaults, options, false);
   setGuttersForLineNumbers(options);
   var doc = options.value;
   if (typeof doc == "string") doc = new Doc(doc, options.mode, null, options.lineSeparator);
   this.doc = doc;
   var input = new CodeMirror.inputStyles[options.inputStyle](this);
   var display = this.display = new Display(place, doc, input);
   display.wrapper.CodeMirror = this;
   updateGutters(this);
   themeChanged(this);
   if (options.lineWrapping)
     this.display.wrapper.className += " CodeMirror-wrap";
   if (options.autofocus && !mobile) display.input.focus();
   initScrollbars(this);
   this.state = {
     keyMaps: [],  // stores maps added by addKeyMap
     overlays: [], // highlighting overlays, as added by addOverlay
     modeGen: 0,   // bumped when mode/overlay changes, used to invalidate highlighting info
     overwrite: false,
     delayingBlurEvent: false,
     focused: false,
     suppressEdits: false, // used to disable editing during key handlers when in readOnly mode
     pasteIncoming: false, cutIncoming: false, // help recognize paste/cut edits in input.poll
     selectingText: false,
     draggingText: false,
     highlight: new Delayed(), // stores highlight worker timeout
     keySeq: null,  // Unfinished key sequence
     specialChars: null
   };
   var cm = this;
   // Override magic textarea content restore that IE sometimes does
   // on our hidden textarea on reload
   if (ie && ie_version < 11) setTimeout(function() { cm.display.input.reset(true); }, 20);
   registerEventHandlers(this);
   ensureGlobalHandlers();
   startOperation(this);
   this.curOp.forceUpdate = true;
   attachDoc(this, doc);
   if ((options.autofocus && !mobile) || cm.hasFocus())
     setTimeout(bind(onFocus, this), 20);
   else
     onBlur(this);
   for (var opt in optionHandlers) if (optionHandlers.hasOwnProperty(opt))
     optionHandlers[opt](this, options[opt], Init);
   maybeUpdateLineNumberWidth(this);
   if (options.finishInit) options.finishInit(this);
   for (var i = 0; i < initHooks.length; ++i) initHooks[i](this);
   endOperation(this);
   // Suppress optimizelegibility in Webkit, since it breaks text
   // measuring on line wrapping boundaries.
   if (webkit && options.lineWrapping &&
       getComputedStyle(display.lineDiv).textRendering == "optimizelegibility")
     display.lineDiv.style.textRendering = "auto";
 }
 // DISPLAY CONSTRUCTOR
 // The display handles the DOM integration, both for input reading
 // and content drawing. It holds references to DOM nodes and
 // display-related state.
 function Display(place, doc, input) {
   var d = this;
   this.input = input;
   // Covers bottom-right square when both scrollbars are present.
   d.scrollbarFiller = elt("div", null, "CodeMirror-scrollbar-filler");
   d.scrollbarFiller.setAttribute("cm-not-content", "true");
   // Covers bottom of gutter when coverGutterNextToScrollbar is on
   // and h scrollbar is present.
   d.gutterFiller = elt("div", null, "CodeMirror-gutter-filler");
   d.gutterFiller.setAttribute("cm-not-content", "true");
   // Will contain the actual code, positioned to cover the viewport.
   d.lineDiv = elt("div", null, "CodeMirror-code");
   // Elements are added to these to represent selection and cursors.
   d.selectionDiv = elt("div", null, null, "position: relative; z-index: 1");
   d.cursorDiv = elt("div", null, "CodeMirror-cursors");
   // A visibility: hidden element used to find the size of things.
   d.measure = elt("div", null, "CodeMirror-measure");
   // When lines outside of the viewport are measured, they are drawn in this.
   d.lineMeasure = elt("div", null, "CodeMirror-measure");
   // Wraps everything that needs to exist inside the vertically-padded coordinate system
   d.lineSpace = elt("div", [d.measure, d.lineMeasure, d.selectionDiv, d.cursorDiv, d.lineDiv],
                     null, "position: relative; outline: none");
   // Moved around its parent to cover visible view.
   d.mover = elt("div", [elt("div", [d.lineSpace], "CodeMirror-lines")], null, "position: relative");
   // Set to the height of the document, allowing scrolling.
   d.sizer = elt("div", [d.mover], "CodeMirror-sizer");
   d.sizerWidth = null;
   // Behavior of elts with overflow: auto and padding is
   // inconsistent across browsers. This is used to ensure the
   // scrollable area is big enough.
   d.heightForcer = elt("div", null, null, "position: absolute; height: " + scrollerGap + "px; width: 1px;");
   // Will contain the gutters, if any.
   d.gutters = elt("div", null, "CodeMirror-gutters");
   d.lineGutter = null;
   // Actual scrollable element.
   d.scroller = elt("div", [d.sizer, d.heightForcer, d.gutters], "CodeMirror-scroll");
   d.scroller.setAttribute("tabIndex", "-1");
   // The element in which the editor lives.
   d.wrapper = elt("div", [d.scrollbarFiller, d.gutterFiller, d.scroller], "CodeMirror");
   // Work around IE7 z-index bug (not perfect, hence IE7 not really being supported)
   if (ie && ie_version < 8) { d.gutters.style.zIndex = -1; d.scroller.style.paddingRight = 0; }
   if (!webkit && !(gecko && mobile)) d.scroller.draggable = true;
   if (place) {
     if (place.appendChild) place.appendChild(d.wrapper);
     else place(d.wrapper);
   }
   // Current rendered range (may be bigger than the view window).
   d.viewFrom = d.viewTo = doc.first;
   d.reportedViewFrom = d.reportedViewTo = doc.first;
   // Information about the rendered lines.
   d.view = [];
   d.renderedView = null;
   // Holds info about a single rendered line when it was rendered
   // for measurement, while not in view.
   d.externalMeasured = null;
   // Empty space (in pixels) above the view
   d.viewOffset = 0;
   d.lastWrapHeight = d.lastWrapWidth = 0;
   d.updateLineNumbers = null;
   d.nativeBarWidth = d.barHeight = d.barWidth = 0;
   d.scrollbarsClipped = false;
   // Used to only resize the line number gutter when necessary (when
   // the amount of lines crosses a boundary that makes its width change)
   d.lineNumWidth = d.lineNumInnerWidth = d.lineNumChars = null;
   // Set to true when a non-horizontal-scrolling line widget is
   // added. As an optimization, line widget aligning is skipped when
   // this is false.
   d.alignWidgets = false;
   d.cachedCharWidth = d.cachedTextHeight = d.cachedPaddingH = null;
   // Tracks the maximum line length so that the horizontal scrollbar
   // can be kept static when scrolling.
   d.maxLine = null;
   d.maxLineLength = 0;
   d.maxLineChanged = false;
   // Used for measuring wheel scrolling granularity
   d.wheelDX = d.wheelDY = d.wheelStartX = d.wheelStartY = null;
   // True when shift is held down.
   d.shift = false;
   // Used to track whether anything happened since the context menu
   // was opened.
   d.selForContextMenu = null;
   d.activeTouch = null;
   input.init(d);
 }
 // STATE UPDATES
 // Used to get the editor into a consistent state again when options change.
 function loadMode(cm) {
   cm.doc.mode = CodeMirror.getMode(cm.options, cm.doc.modeOption);
   resetModeState(cm);
 }
 function resetModeState(cm) {
   cm.doc.iter(function(line) {
     if (line.stateAfter) line.stateAfter = null;
     if (line.styles) line.styles = null;
   });
   cm.doc.frontier = cm.doc.first;
   startWorker(cm, 100);
   cm.state.modeGen++;
   if (cm.curOp) regChange(cm);
 }
 function wrappingChanged(cm) {
   if (cm.options.lineWrapping) {
     addClass(cm.display.wrapper, "CodeMirror-wrap");
     cm.display.sizer.style.minWidth = "";
     cm.display.sizerWidth = null;
   } else {
     rmClass(cm.display.wrapper, "CodeMirror-wrap");
     findMaxLine(cm);
   }
   estimateLineHeights(cm);
   regChange(cm);
   clearCaches(cm);
   setTimeout(function(){updateScrollbars(cm);}, 100);
 }
 // Returns a function that estimates the height of a line, to use as
 // first approximation until the line becomes visible (and is thus
 // properly measurable).
 function estimateHeight(cm) {
   var th = textHeight(cm.display), wrapping = cm.options.lineWrapping;
   var perLine = wrapping && Math.max(5, cm.display.scroller.clientWidth / charWidth(cm.display) - 3);
   return function(line) {
     if (lineIsHidden(cm.doc, line)) return 0;
     var widgetsHeight = 0;
     if (line.widgets) for (var i = 0; i < line.widgets.length; i++) {
       if (line.widgets[i].height) widgetsHeight += line.widgets[i].height;
     }
     if (wrapping)
       return widgetsHeight + (Math.ceil(line.text.length / perLine) || 1) * th;
     else
       return widgetsHeight + th;
   };
 }
 function estimateLineHeights(cm) {
   var doc = cm.doc, est = estimateHeight(cm);
   doc.iter(function(line) {
     var estHeight = est(line);
     if (estHeight != line.height) updateLineHeight(line, estHeight);
   });
 }
 function themeChanged(cm) {
   cm.display.wrapper.className = cm.display.wrapper.className.replace(/\s*cm-s-\S+/g, "") +
     cm.options.theme.replace(/(^|\s)\s*/g, " cm-s-");
   clearCaches(cm);
 }
 function guttersChanged(cm) {
   updateGutters(cm);
   regChange(cm);
   setTimeout(function(){alignHorizontally(cm);}, 20);
 }
 // Rebuild the gutter elements, ensure the margin to the left of the
 // code matches their width.
 function updateGutters(cm) {
   var gutters = cm.display.gutters, specs = cm.options.gutters;
   removeChildren(gutters);
   for (var i = 0; i < specs.length; ++i) {
     var gutterClass = specs[i];
     var gElt = gutters.appendChild(elt("div", null, "CodeMirror-gutter " + gutterClass));
     if (gutterClass == "CodeMirror-linenumbers") {
       cm.display.lineGutter = gElt;
       gElt.style.width = (cm.display.lineNumWidth || 1) + "px";
     }
   }
   gutters.style.display = i ? "" : "none";
   updateGutterSpace(cm);
 }
 function updateGutterSpace(cm) {
   var width = cm.display.gutters.offsetWidth;
   cm.display.sizer.style.marginLeft = width + "px";
 }
 // Compute the character length of a line, taking into account
 // collapsed ranges (see markText) that might hide parts, and join
 // other lines onto it.
 function lineLength(line) {
   if (line.height == 0) return 0;
   var len = line.text.length, merged, cur = line;
   while (merged = collapsedSpanAtStart(cur)) {
     var found = merged.find(0, true);
     cur = found.from.line;
     len += found.from.ch - found.to.ch;
   }
   cur = line;
   while (merged = collapsedSpanAtEnd(cur)) {
     var found = merged.find(0, true);
     len -= cur.text.length - found.from.ch;
     cur = found.to.line;
     len += cur.text.length - found.to.ch;
   }
   return len;
 }
 // Find the longest line in the document.
 function findMaxLine(cm) {
   var d = cm.display, doc = cm.doc;
   d.maxLine = getLine(doc, doc.first);
   d.maxLineLength = lineLength(d.maxLine);
   d.maxLineChanged = true;
   doc.iter(function(line) {
     var len = lineLength(line);
     if (len > d.maxLineLength) {
       d.maxLineLength = len;
       d.maxLine = line;
     }
   });
 }
 // Make sure the gutters options contains the element
 // "CodeMirror-linenumbers" when the lineNumbers option is true.
 function setGuttersForLineNumbers(options) {
   var found = indexOf(options.gutters, "CodeMirror-linenumbers");
   if (found == -1 && options.lineNumbers) {
     options.gutters = options.gutters.concat(["CodeMirror-linenumbers"]);
   } else if (found > -1 && !options.lineNumbers) {
     options.gutters = options.gutters.slice(0);
     options.gutters.splice(found, 1);
   }
 }
 // SCROLLBARS
 // Prepare DOM reads needed to update the scrollbars. Done in one
 // shot to minimize update/measure roundtrips.
 function measureForScrollbars(cm) {
   var d = cm.display, gutterW = d.gutters.offsetWidth;
   var docH = Math.round(cm.doc.height + paddingVert(cm.display));
   return {
     clientHeight: d.scroller.clientHeight,
     viewHeight: d.wrapper.clientHeight,
     scrollWidth: d.scroller.scrollWidth, clientWidth: d.scroller.clientWidth,
     viewWidth: d.wrapper.clientWidth,
     barLeft: cm.options.fixedGutter ? gutterW : 0,
     docHeight: docH,
     scrollHeight: docH + scrollGap(cm) + d.barHeight,
     nativeBarWidth: d.nativeBarWidth,
     gutterWidth: gutterW
   };
 }
 function NativeScrollbars(place, scroll, cm) {
   this.cm = cm;
   var vert = this.vert = elt("div", [elt("div", null, null, "min-width: 1px")], "CodeMirror-vscrollbar");
   var horiz = this.horiz = elt("div", [elt("div", null, null, "height: 100%; min-height: 1px")], "CodeMirror-hscrollbar");
   place(vert); place(horiz);
   on(vert, "scroll", function() {
     if (vert.clientHeight) scroll(vert.scrollTop, "vertical");
   });
   on(horiz, "scroll", function() {
     if (horiz.clientWidth) scroll(horiz.scrollLeft, "horizontal");
   });
   this.checkedOverlay = false;
   // Need to set a minimum width to see the scrollbar on IE7 (but must not set it on IE8).
   if (ie && ie_version < 8) this.horiz.style.minHeight = this.vert.style.minWidth = "18px";
 }
 NativeScrollbars.prototype = copyObj({
   update: function(measure) {
     var needsH = measure.scrollWidth > measure.clientWidth + 1;
     var needsV = measure.scrollHeight > measure.clientHeight + 1;
     var sWidth = measure.nativeBarWidth;
     if (needsV) {
       this.vert.style.display = "block";
       this.vert.style.bottom = needsH ? sWidth + "px" : "0";
       var totalHeight = measure.viewHeight - (needsH ? sWidth : 0);
       // A bug in IE8 can cause this value to be negative, so guard it.
       this.vert.firstChild.style.height =
         Math.max(0, measure.scrollHeight - measure.clientHeight + totalHeight) + "px";
     } else {
       this.vert.style.display = "";
       this.vert.firstChild.style.height = "0";
     }
     if (needsH) {
       this.horiz.style.display = "block";
       this.horiz.style.right = needsV ? sWidth + "px" : "0";
       this.horiz.style.left = measure.barLeft + "px";
       var totalWidth = measure.viewWidth - measure.barLeft - (needsV ? sWidth : 0);
       this.horiz.firstChild.style.width =
         (measure.scrollWidth - measure.clientWidth + totalWidth) + "px";
     } else {
       this.horiz.style.display = "";
       this.horiz.firstChild.style.width = "0";
     }
     if (!this.checkedOverlay && measure.clientHeight > 0) {
       if (sWidth == 0) this.overlayHack();
       this.checkedOverlay = true;
     }
     return {right: needsV ? sWidth : 0, bottom: needsH ? sWidth : 0};
   },
   setScrollLeft: function(pos) {
     if (this.horiz.scrollLeft != pos) this.horiz.scrollLeft = pos;
   },
   setScrollTop: function(pos) {
     if (this.vert.scrollTop != pos) this.vert.scrollTop = pos;
   },
   overlayHack: function() {
     var w = mac && !mac_geMountainLion ? "12px" : "18px";
     this.horiz.style.minHeight = this.vert.style.minWidth = w;
     var self = this;
     var barMouseDown = function(e) {
       if (e_target(e) != self.vert && e_target(e) != self.horiz)
         operation(self.cm, onMouseDown)(e);
     };
     on(this.vert, "mousedown", barMouseDown);
     on(this.horiz, "mousedown", barMouseDown);
   },
   clear: function() {
     var parent = this.horiz.parentNode;
     parent.removeChild(this.horiz);
     parent.removeChild(this.vert);
   }
 }, NativeScrollbars.prototype);
 function NullScrollbars() {}
 NullScrollbars.prototype = copyObj({
   update: function() { return {bottom: 0, right: 0}; },
   setScrollLeft: function() {},
   setScrollTop: function() {},
   clear: function() {}
 }, NullScrollbars.prototype);
 CodeMirror.scrollbarModel = {"native": NativeScrollbars, "null": NullScrollbars};
 function initScrollbars(cm) {
   if (cm.display.scrollbars) {
     cm.display.scrollbars.clear();
     if (cm.display.scrollbars.addClass)
       rmClass(cm.display.wrapper, cm.display.scrollbars.addClass);
   }
   cm.display.scrollbars = new CodeMirror.scrollbarModel[cm.options.scrollbarStyle](function(node) {
     cm.display.wrapper.insertBefore(node, cm.display.scrollbarFiller);
     // Prevent clicks in the scrollbars from killing focus
     on(node, "mousedown", function() {
       if (cm.state.focused) setTimeout(function() { cm.display.input.focus(); }, 0);
     });
     node.setAttribute("cm-not-content", "true");
   }, function(pos, axis) {
     if (axis == "horizontal") setScrollLeft(cm, pos);
     else setScrollTop(cm, pos);
   }, cm);
   if (cm.display.scrollbars.addClass)
     addClass(cm.display.wrapper, cm.display.scrollbars.addClass);
 }
 function updateScrollbars(cm, measure) {
   if (!measure) measure = measureForScrollbars(cm);
   var startWidth = cm.display.barWidth, startHeight = cm.display.barHeight;
   updateScrollbarsInner(cm, measure);
   for (var i = 0; i < 4 && startWidth != cm.display.barWidth || startHeight != cm.display.barHeight; i++) {
     if (startWidth != cm.display.barWidth && cm.options.lineWrapping)
       updateHeightsInViewport(cm);
     updateScrollbarsInner(cm, measureForScrollbars(cm));
     startWidth = cm.display.barWidth; startHeight = cm.display.barHeight;
   }
 }
 // Re-synchronize the fake scrollbars with the actual size of the
 // content.
 function updateScrollbarsInner(cm, measure) {
   var d = cm.display;
   var sizes = d.scrollbars.update(measure);
   d.sizer.style.paddingRight = (d.barWidth = sizes.right) + "px";
   d.sizer.style.paddingBottom = (d.barHeight = sizes.bottom) + "px";
   if (sizes.right && sizes.bottom) {
     d.scrollbarFiller.style.display = "block";
     d.scrollbarFiller.style.height = sizes.bottom + "px";
     d.scrollbarFiller.style.width = sizes.right + "px";
   } else d.scrollbarFiller.style.display = "";
   if (sizes.bottom && cm.options.coverGutterNextToScrollbar && cm.options.fixedGutter) {
     d.gutterFiller.style.display = "block";
     d.gutterFiller.style.height = sizes.bottom + "px";
     d.gutterFiller.style.width = measure.gutterWidth + "px";
   } else d.gutterFiller.style.display = "";
 }
 // Compute the lines that are visible in a given viewport (defaults
 // the the current scroll position). viewport may contain top,
 // height, and ensure (see op.scrollToPos) properties.
 function visibleLines(display, doc, viewport) {
   var top = viewport && viewport.top != null ? Math.max(0, viewport.top) : display.scroller.scrollTop;
   top = Math.floor(top - paddingTop(display));
   var bottom = viewport && viewport.bottom != null ? viewport.bottom : top + display.wrapper.clientHeight;
   var from = lineAtHeight(doc, top), to = lineAtHeight(doc, bottom);
   // Ensure is a {from: {line, ch}, to: {line, ch}} object, and
   // forces those lines into the viewport (if possible).
   if (viewport && viewport.ensure) {
     var ensureFrom = viewport.ensure.from.line, ensureTo = viewport.ensure.to.line;
     if (ensureFrom < from) {
       from = ensureFrom;
       to = lineAtHeight(doc, heightAtLine(getLine(doc, ensureFrom)) + display.wrapper.clientHeight);
     } else if (Math.min(ensureTo, doc.lastLine()) >= to) {
       from = lineAtHeight(doc, heightAtLine(getLine(doc, ensureTo)) - display.wrapper.clientHeight);
       to = ensureTo;
     }
   }
   return {from: from, to: Math.max(to, from + 1)};
 }
 // LINE NUMBERS
 // Re-align line numbers and gutter marks to compensate for
 // horizontal scrolling.
 function alignHorizontally(cm) {
   var display = cm.display, view = display.view;
   if (!display.alignWidgets && (!display.gutters.firstChild || !cm.options.fixedGutter)) return;
   var comp = compensateForHScroll(display) - display.scroller.scrollLeft + cm.doc.scrollLeft;
   var gutterW = display.gutters.offsetWidth, left = comp + "px";
   for (var i = 0; i < view.length; i++) if (!view[i].hidden) {
     if (cm.options.fixedGutter && view[i].gutter)
       view[i].gutter.style.left = left;
     var align = view[i].alignable;
     if (align) for (var j = 0; j < align.length; j++)
       align[j].style.left = left;
   }
   if (cm.options.fixedGutter)
     display.gutters.style.left = (comp + gutterW) + "px";
 }
 // Used to ensure that the line number gutter is still the right
 // size for the current document size. Returns true when an update
 // is needed.
 function maybeUpdateLineNumberWidth(cm) {
   if (!cm.options.lineNumbers) return false;
   var doc = cm.doc, last = lineNumberFor(cm.options, doc.first + doc.size - 1), display = cm.display;
   if (last.length != display.lineNumChars) {
     var test = display.measure.appendChild(elt("div", [elt("div", last)],
                                                "CodeMirror-linenumber CodeMirror-gutter-elt"));
     var innerW = test.firstChild.offsetWidth, padding = test.offsetWidth - innerW;
     display.lineGutter.style.width = "";
     display.lineNumInnerWidth = Math.max(innerW, display.lineGutter.offsetWidth - padding) + 1;
     display.lineNumWidth = display.lineNumInnerWidth + padding;
     display.lineNumChars = display.lineNumInnerWidth ? last.length : -1;
     display.lineGutter.style.width = display.lineNumWidth + "px";
     updateGutterSpace(cm);
     return true;
   }
   return false;
 }
 function lineNumberFor(options, i) {
   return String(options.lineNumberFormatter(i + options.firstLineNumber));
 }
 // Computes display.scroller.scrollLeft + display.gutters.offsetWidth,
 // but using getBoundingClientRect to get a sub-pixel-accurate
 // result.
 function compensateForHScroll(display) {
   return display.scroller.getBoundingClientRect().left - display.sizer.getBoundingClientRect().left;
 }
 // DISPLAY DRAWING
 function DisplayUpdate(cm, viewport, force) {
   var display = cm.display;
   this.viewport = viewport;
   // Store some values that we'll need later (but don't want to force a relayout for)
   this.visible = visibleLines(display, cm.doc, viewport);
   this.editorIsHidden = !display.wrapper.offsetWidth;
   this.wrapperHeight = display.wrapper.clientHeight;
   this.wrapperWidth = display.wrapper.clientWidth;
   this.oldDisplayWidth = displayWidth(cm);
   this.force = force;
   this.dims = getDimensions(cm);
   this.events = [];
 }
 DisplayUpdate.prototype.signal = function(emitter, type) {
   if (hasHandler(emitter, type))
     this.events.push(arguments);
 };
 DisplayUpdate.prototype.finish = function() {
   for (var i = 0; i < this.events.length; i++)
     signal.apply(null, this.events[i]);
 };
 function maybeClipScrollbars(cm) {
   var display = cm.display;
   if (!display.scrollbarsClipped && display.scroller.offsetWidth) {
     display.nativeBarWidth = display.scroller.offsetWidth - display.scroller.clientWidth;
     display.heightForcer.style.height = scrollGap(cm) + "px";
     display.sizer.style.marginBottom = -display.nativeBarWidth + "px";
     display.sizer.style.borderRightWidth = scrollGap(cm) + "px";
     display.scrollbarsClipped = true;
   }
 }
 // Does the actual updating of the line display. Bails out
 // (returning false) when there is nothing to be done and forced is
 // false.
 function updateDisplayIfNeeded(cm, update) {
   var display = cm.display, doc = cm.doc;
   if (update.editorIsHidden) {
     resetView(cm);
     return false;
   }
   // Bail out if the visible area is already rendered and nothing changed.
   if (!update.force &&
       update.visible.from >= display.viewFrom && update.visible.to <= display.viewTo &&
       (display.updateLineNumbers == null || display.updateLineNumbers >= display.viewTo) &&
       display.renderedView == display.view && countDirtyView(cm) == 0)
     return false;
   if (maybeUpdateLineNumberWidth(cm)) {
     resetView(cm);
     update.dims = getDimensions(cm);
   }
   // Compute a suitable new viewport (from & to)
   var end = doc.first + doc.size;
   var from = Math.max(update.visible.from - cm.options.viewportMargin, doc.first);
   var to = Math.min(end, update.visible.to + cm.options.viewportMargin);
   if (display.viewFrom < from && from - display.viewFrom < 20) from = Math.max(doc.first, display.viewFrom);
   if (display.viewTo > to && display.viewTo - to < 20) to = Math.min(end, display.viewTo);
   if (sawCollapsedSpans) {
     from = visualLineNo(cm.doc, from);
     to = visualLineEndNo(cm.doc, to);
   }
   var different = from != display.viewFrom || to != display.viewTo ||
     display.lastWrapHeight != update.wrapperHeight || display.lastWrapWidth != update.wrapperWidth;
   adjustView(cm, from, to);
   display.viewOffset = heightAtLine(getLine(cm.doc, display.viewFrom));
   // Position the mover div to align with the current scroll position
   cm.display.mover.style.top = display.viewOffset + "px";
   var toUpdate = countDirtyView(cm);
   if (!different && toUpdate == 0 && !update.force && display.renderedView == display.view &&
       (display.updateLineNumbers == null || display.updateLineNumbers >= display.viewTo))
     return false;
   // For big changes, we hide the enclosing element during the
   // update, since that speeds up the operations on most browsers.
   var focused = activeElt();
   if (toUpdate > 4) display.lineDiv.style.display = "none";
   patchDisplay(cm, display.updateLineNumbers, update.dims);
   if (toUpdate > 4) display.lineDiv.style.display = "";
   display.renderedView = display.view;
   // There might have been a widget with a focused element that got
   // hidden or updated, if so re-focus it.
   if (focused && activeElt() != focused && focused.offsetHeight) focused.focus();
   // Prevent selection and cursors from interfering with the scroll
   // width and height.
   removeChildren(display.cursorDiv);
   removeChildren(display.selectionDiv);
   display.gutters.style.height = display.sizer.style.minHeight = 0;
   if (different) {
     display.lastWrapHeight = update.wrapperHeight;
     display.lastWrapWidth = update.wrapperWidth;
     startWorker(cm, 400);
   }
   display.updateLineNumbers = null;
   return true;
 }
 function postUpdateDisplay(cm, update) {
   var viewport = update.viewport;
   for (var first = true;; first = false) {
     if (!first || !cm.options.lineWrapping || update.oldDisplayWidth == displayWidth(cm)) {
       // Clip forced viewport to actual scrollable area.
       if (viewport && viewport.top != null)
         viewport = {top: Math.min(cm.doc.height + paddingVert(cm.display) - displayHeight(cm), viewport.top)};
       // Updated line heights might result in the drawn area not
       // actually covering the viewport. Keep looping until it does.
       update.visible = visibleLines(cm.display, cm.doc, viewport);
       if (update.visible.from >= cm.display.viewFrom && update.visible.to <= cm.display.viewTo)
         break;
     }
     if (!updateDisplayIfNeeded(cm, update)) break;
     updateHeightsInViewport(cm);
     var barMeasure = measureForScrollbars(cm);
     updateSelection(cm);
     setDocumentHeight(cm, barMeasure);
     updateScrollbars(cm, barMeasure);
   }
   update.signal(cm, "update", cm);
   if (cm.display.viewFrom != cm.display.reportedViewFrom || cm.display.viewTo != cm.display.reportedViewTo) {
     update.signal(cm, "viewportChange", cm, cm.display.viewFrom, cm.display.viewTo);
     cm.display.reportedViewFrom = cm.display.viewFrom; cm.display.reportedViewTo = cm.display.viewTo;
   }
 }
 function updateDisplaySimple(cm, viewport) {
   var update = new DisplayUpdate(cm, viewport);
   if (updateDisplayIfNeeded(cm, update)) {
     updateHeightsInViewport(cm);
     postUpdateDisplay(cm, update);
     var barMeasure = measureForScrollbars(cm);
     updateSelection(cm);
     setDocumentHeight(cm, barMeasure);
     updateScrollbars(cm, barMeasure);
     update.finish();
   }
 }
 function setDocumentHeight(cm, measure) {
   cm.display.sizer.style.minHeight = measure.docHeight + "px";
   var total = measure.docHeight + cm.display.barHeight;
   cm.display.heightForcer.style.top = total + "px";
   cm.display.gutters.style.height = Math.max(total + scrollGap(cm), measure.clientHeight) + "px";
 }
 // Read the actual heights of the rendered lines, and update their
 // stored heights to match.
 function updateHeightsInViewport(cm) {
   var display = cm.display;
   var prevBottom = display.lineDiv.offsetTop;
   for (var i = 0; i < display.view.length; i++) {
     var cur = display.view[i], height;
     if (cur.hidden) continue;
     if (ie && ie_version < 8) {
       var bot = cur.node.offsetTop + cur.node.offsetHeight;
       height = bot - prevBottom;
       prevBottom = bot;
     } else {
       var box = cur.node.getBoundingClientRect();
       height = box.bottom - box.top;
     }
     var diff = cur.line.height - height;
     if (height < 2) height = textHeight(display);
     if (diff > .001 || diff < -.001) {
       updateLineHeight(cur.line, height);
       updateWidgetHeight(cur.line);
       if (cur.rest) for (var j = 0; j < cur.rest.length; j++)
         updateWidgetHeight(cur.rest[j]);
     }
   }
 }
 // Read and store the height of line widgets associated with the
 // given line.
 function updateWidgetHeight(line) {
   if (line.widgets) for (var i = 0; i < line.widgets.length; ++i)
     line.widgets[i].height = line.widgets[i].node.offsetHeight;
 }
 // Do a bulk-read of the DOM positions and sizes needed to draw the
 // view, so that we don't interleave reading and writing to the DOM.
 function getDimensions(cm) {
   var d = cm.display, left = {}, width = {};
   var gutterLeft = d.gutters.clientLeft;
   for (var n = d.gutters.firstChild, i = 0; n; n = n.nextSibling, ++i) {
     left[cm.options.gutters[i]] = n.offsetLeft + n.clientLeft + gutterLeft;
     width[cm.options.gutters[i]] = n.clientWidth;
   }
   return {fixedPos: compensateForHScroll(d),
           gutterTotalWidth: d.gutters.offsetWidth,
           gutterLeft: left,
           gutterWidth: width,
           wrapperWidth: d.wrapper.clientWidth};
 }
 // Sync the actual display DOM structure with display.view, removing
 // nodes for lines that are no longer in view, and creating the ones
 // that are not there yet, and updating the ones that are out of
 // date.
 function patchDisplay(cm, updateNumbersFrom, dims) {
   var display = cm.display, lineNumbers = cm.options.lineNumbers;
   var container = display.lineDiv, cur = container.firstChild;
   function rm(node) {
     var next = node.nextSibling;
     // Works around a throw-scroll bug in OS X Webkit
     if (webkit && mac && cm.display.currentWheelTarget == node)
       node.style.display = "none";
     else
       node.parentNode.removeChild(node);
     return next;
   }
   var view = display.view, lineN = display.viewFrom;
   // Loop over the elements in the view, syncing cur (the DOM nodes
   // in display.lineDiv) with the view as we go.
   for (var i = 0; i < view.length; i++) {
     var lineView = view[i];
     if (lineView.hidden) {
     } else if (!lineView.node || lineView.node.parentNode != container) { // Not drawn yet
       var node = buildLineElement(cm, lineView, lineN, dims);
       container.insertBefore(node, cur);
     } else { // Already drawn
       while (cur != lineView.node) cur = rm(cur);
       var updateNumber = lineNumbers && updateNumbersFrom != null &&
         updateNumbersFrom <= lineN && lineView.lineNumber;
       if (lineView.changes) {
         if (indexOf(lineView.changes, "gutter") > -1) updateNumber = false;
         updateLineForChanges(cm, lineView, lineN, dims);
       }
       if (updateNumber) {
         removeChildren(lineView.lineNumber);
         lineView.lineNumber.appendChild(document.createTextNode(lineNumberFor(cm.options, lineN)));
       }
       cur = lineView.node.nextSibling;
     }
     lineN += lineView.size;
   }
   while (cur) cur = rm(cur);
 }
 // When an aspect of a line changes, a string is added to
 // lineView.changes. This updates the relevant part of the line's
 // DOM structure.
 function updateLineForChanges(cm, lineView, lineN, dims) {
   for (var j = 0; j < lineView.changes.length; j++) {
     var type = lineView.changes[j];
     if (type == "text") updateLineText(cm, lineView);
     else if (type == "gutter") updateLineGutter(cm, lineView, lineN, dims);
     else if (type == "class") updateLineClasses(lineView);
     else if (type == "widget") updateLineWidgets(cm, lineView, dims);
   }
   lineView.changes = null;
 }
 // Lines with gutter elements, widgets or a background class need to
 // be wrapped, and have the extra elements added to the wrapper div
 function ensureLineWrapped(lineView) {
   if (lineView.node == lineView.text) {
     lineView.node = elt("div", null, null, "position: relative");
     if (lineView.text.parentNode)
       lineView.text.parentNode.replaceChild(lineView.node, lineView.text);
     lineView.node.appendChild(lineView.text);
     if (ie && ie_version < 8) lineView.node.style.zIndex = 2;
   }
   return lineView.node;
 }
 function updateLineBackground(lineView) {
   var cls = lineView.bgClass ? lineView.bgClass + " " + (lineView.line.bgClass || "") : lineView.line.bgClass;
   if (cls) cls += " CodeMirror-linebackground";
   if (lineView.background) {
     if (cls) lineView.background.className = cls;
     else { lineView.background.parentNode.removeChild(lineView.background); lineView.background = null; }
   } else if (cls) {
     var wrap = ensureLineWrapped(lineView);
     lineView.background = wrap.insertBefore(elt("div", null, cls), wrap.firstChild);
   }
 }
 // Wrapper around buildLineContent which will reuse the structure
 // in display.externalMeasured when possible.
 function getLineContent(cm, lineView) {
   var ext = cm.display.externalMeasured;
   if (ext && ext.line == lineView.line) {
     cm.display.externalMeasured = null;
     lineView.measure = ext.measure;
     return ext.built;
   }
   return buildLineContent(cm, lineView);
 }
 // Redraw the line's text. Interacts with the background and text
 // classes because the mode may output tokens that influence these
 // classes.
 function updateLineText(cm, lineView) {
   var cls = lineView.text.className;
   var built = getLineContent(cm, lineView);
   if (lineView.text == lineView.node) lineView.node = built.pre;
   lineView.text.parentNode.replaceChild(built.pre, lineView.text);
   lineView.text = built.pre;
   if (built.bgClass != lineView.bgClass || built.textClass != lineView.textClass) {
     lineView.bgClass = built.bgClass;
     lineView.textClass = built.textClass;
     updateLineClasses(lineView);
   } else if (cls) {
     lineView.text.className = cls;
   }
 }
 function updateLineClasses(lineView) {
   updateLineBackground(lineView);
   if (lineView.line.wrapClass)
     ensureLineWrapped(lineView).className = lineView.line.wrapClass;
   else if (lineView.node != lineView.text)
     lineView.node.className = "";
   var textClass = lineView.textClass ? lineView.textClass + " " + (lineView.line.textClass || "") : lineView.line.textClass;
   lineView.text.className = textClass || "";
 }
 function updateLineGutter(cm, lineView, lineN, dims) {
   if (lineView.gutter) {
     lineView.node.removeChild(lineView.gutter);
     lineView.gutter = null;
   }
   if (lineView.gutterBackground) {
     lineView.node.removeChild(lineView.gutterBackground);
     lineView.gutterBackground = null;
   }
   if (lineView.line.gutterClass) {
     var wrap = ensureLineWrapped(lineView);
     lineView.gutterBackground = elt("div", null, "CodeMirror-gutter-background " + lineView.line.gutterClass,
                                     "left: " + (cm.options.fixedGutter ? dims.fixedPos : -dims.gutterTotalWidth) +
                                     "px; width: " + dims.gutterTotalWidth + "px");
     wrap.insertBefore(lineView.gutterBackground, lineView.text);
   }
   var markers = lineView.line.gutterMarkers;
   if (cm.options.lineNumbers || markers) {
     var wrap = ensureLineWrapped(lineView);
     var gutterWrap = lineView.gutter = elt("div", null, "CodeMirror-gutter-wrapper", "left: " +
                                            (cm.options.fixedGutter ? dims.fixedPos : -dims.gutterTotalWidth) + "px");
     cm.display.input.setUneditable(gutterWrap);
     wrap.insertBefore(gutterWrap, lineView.text);
     if (lineView.line.gutterClass)
       gutterWrap.className += " " + lineView.line.gutterClass;
     if (cm.options.lineNumbers && (!markers || !markers["CodeMirror-linenumbers"]))
       lineView.lineNumber = gutterWrap.appendChild(
         elt("div", lineNumberFor(cm.options, lineN),
             "CodeMirror-linenumber CodeMirror-gutter-elt",
             "left: " + dims.gutterLeft["CodeMirror-linenumbers"] + "px; width: "
             + cm.display.lineNumInnerWidth + "px"));
     if (markers) for (var k = 0; k < cm.options.gutters.length; ++k) {
       var id = cm.options.gutters[k], found = markers.hasOwnProperty(id) && markers[id];
       if (found)
         gutterWrap.appendChild(elt("div", [found], "CodeMirror-gutter-elt", "left: " +
                                    dims.gutterLeft[id] + "px; width: " + dims.gutterWidth[id] + "px"));
     }
   }
 }
 function updateLineWidgets(cm, lineView, dims) {
   if (lineView.alignable) lineView.alignable = null;
   for (var node = lineView.node.firstChild, next; node; node = next) {
     var next = node.nextSibling;
     if (node.className == "CodeMirror-linewidget")
       lineView.node.removeChild(node);
   }
   insertLineWidgets(cm, lineView, dims);
 }
 // Build a line's DOM representation from scratch
 function buildLineElement(cm, lineView, lineN, dims) {
   var built = getLineContent(cm, lineView);
   lineView.text = lineView.node = built.pre;
   if (built.bgClass) lineView.bgClass = built.bgClass;
   if (built.textClass) lineView.textClass = built.textClass;
   updateLineClasses(lineView);
   updateLineGutter(cm, lineView, lineN, dims);
   insertLineWidgets(cm, lineView, dims);
   return lineView.node;
 }
 // A lineView may contain multiple logical lines (when merged by
 // collapsed spans). The widgets for all of them need to be drawn.
 function insertLineWidgets(cm, lineView, dims) {
   insertLineWidgetsFor(cm, lineView.line, lineView, dims, true);
   if (lineView.rest) for (var i = 0; i < lineView.rest.length; i++)
     insertLineWidgetsFor(cm, lineView.rest[i], lineView, dims, false);
 }
 function insertLineWidgetsFor(cm, line, lineView, dims, allowAbove) {
   if (!line.widgets) return;
   var wrap = ensureLineWrapped(lineView);
   for (var i = 0, ws = line.widgets; i < ws.length; ++i) {
     var widget = ws[i], node = elt("div", [widget.node], "CodeMirror-linewidget");
     if (!widget.handleMouseEvents) node.setAttribute("cm-ignore-events", "true");
     positionLineWidget(widget, node, lineView, dims);
     cm.display.input.setUneditable(node);
     if (allowAbove && widget.above)
       wrap.insertBefore(node, lineView.gutter || lineView.text);
     else
       wrap.appendChild(node);
     signalLater(widget, "redraw");
   }
 }
 function positionLineWidget(widget, node, lineView, dims) {
   if (widget.noHScroll) {
     (lineView.alignable || (lineView.alignable = [])).push(node);
     var width = dims.wrapperWidth;
     node.style.left = dims.fixedPos + "px";
     if (!widget.coverGutter) {
       width -= dims.gutterTotalWidth;
       node.style.paddingLeft = dims.gutterTotalWidth + "px";
     }
     node.style.width = width + "px";
   }
   if (widget.coverGutter) {
     node.style.zIndex = 5;
     node.style.position = "relative";
     if (!widget.noHScroll) node.style.marginLeft = -dims.gutterTotalWidth + "px";
   }
 }
 // POSITION OBJECT
 // A Pos instance represents a position within the text.
 var Pos = CodeMirror.Pos = function(line, ch) {
   if (!(this instanceof Pos)) return new Pos(line, ch);
   this.line = line; this.ch = ch;
 };
 // Compare two positions, return 0 if they are the same, a negative
 // number when a is less, and a positive number otherwise.
 var cmp = CodeMirror.cmpPos = function(a, b) { return a.line - b.line || a.ch - b.ch; };
 function copyPos(x) {return Pos(x.line, x.ch);}
 function maxPos(a, b) { return cmp(a, b) < 0 ? b : a; }
 function minPos(a, b) { return cmp(a, b) < 0 ? a : b; }
 // INPUT HANDLING
 function ensureFocus(cm) {
   if (!cm.state.focused) { cm.display.input.focus(); onFocus(cm); }
 }
 function isReadOnly(cm) {
   return cm.options.readOnly || cm.doc.cantEdit;
 }
 // This will be set to an array of strings when copying, so that,
 // when pasting, we know what kind of selections the copied text
 // was made out of.
 var lastCopied = null;
 function applyTextInput(cm, inserted, deleted, sel, origin) {
   var doc = cm.doc;
   cm.display.shift = false;
   if (!sel) sel = doc.sel;
   var paste = cm.state.pasteIncoming || origin == "paste";
   var textLines = doc.splitLines(inserted), multiPaste = null;
   // When pasing N lines into N selections, insert one line per selection
   if (paste && sel.ranges.length > 1) {
     if (lastCopied && lastCopied.join("\n") == inserted) {
       if (sel.ranges.length % lastCopied.length == 0) {
         multiPaste = [];
         for (var i = 0; i < lastCopied.length; i++)
           multiPaste.push(doc.splitLines(lastCopied[i]));
       }
     } else if (textLines.length == sel.ranges.length) {
       multiPaste = map(textLines, function(l) { return [l]; });
     }
   }
   // Normal behavior is to insert the new text into every selection
   for (var i = sel.ranges.length - 1; i >= 0; i--) {
     var range = sel.ranges[i];
     var from = range.from(), to = range.to();
     if (range.empty()) {
       if (deleted && deleted > 0) // Handle deletion
         from = Pos(from.line, from.ch - deleted);
       else if (cm.state.overwrite && !paste) // Handle overwrite
         to = Pos(to.line, Math.min(getLine(doc, to.line).text.length, to.ch + lst(textLines).length));
     }
     var updateInput = cm.curOp.updateInput;
     var changeEvent = {from: from, to: to, text: multiPaste ? multiPaste[i % multiPaste.length] : textLines,
                        origin: origin || (paste ? "paste" : cm.state.cutIncoming ? "cut" : "+input")};
     makeChange(cm.doc, changeEvent);
     signalLater(cm, "inputRead", cm, changeEvent);
   }
   if (inserted && !paste)
     triggerElectric(cm, inserted);
   ensureCursorVisible(cm);
   cm.curOp.updateInput = updateInput;
   cm.curOp.typing = true;
   cm.state.pasteIncoming = cm.state.cutIncoming = false;
 }
 function handlePaste(e, cm) {
   var pasted = e.clipboardData && e.clipboardData.getData("text/plain");
   if (pasted) {
     e.preventDefault();
     if (!isReadOnly(cm) && !cm.options.disableInput)
       runInOp(cm, function() { applyTextInput(cm, pasted, 0, null, "paste"); });
     return true;
   }
 }
 function triggerElectric(cm, inserted) {
   // When an 'electric' character is inserted, immediately trigger a reindent
   if (!cm.options.electricChars || !cm.options.smartIndent) return;
   var sel = cm.doc.sel;
   for (var i = sel.ranges.length - 1; i >= 0; i--) {
     var range = sel.ranges[i];
     if (range.head.ch > 100 || (i && sel.ranges[i - 1].head.line == range.head.line)) continue;
     var mode = cm.getModeAt(range.head);
     var indented = false;
     if (mode.electricChars) {
       for (var j = 0; j < mode.electricChars.length; j++)
         if (inserted.indexOf(mode.electricChars.charAt(j)) > -1) {
           indented = indentLine(cm, range.head.line, "smart");
           break;
         }
     } else if (mode.electricInput) {
       if (mode.electricInput.test(getLine(cm.doc, range.head.line).text.slice(0, range.head.ch)))
         indented = indentLine(cm, range.head.line, "smart");
     }
     if (indented) signalLater(cm, "electricInput", cm, range.head.line);
   }
 }
 function copyableRanges(cm) {
   var text = [], ranges = [];
   for (var i = 0; i < cm.doc.sel.ranges.length; i++) {
     var line = cm.doc.sel.ranges[i].head.line;
     var lineRange = {anchor: Pos(line, 0), head: Pos(line + 1, 0)};
     ranges.push(lineRange);
     text.push(cm.getRange(lineRange.anchor, lineRange.head));
   }
   return {text: text, ranges: ranges};
 }
 function disableBrowserMagic(field) {
   field.setAttribute("autocorrect", "off");
   field.setAttribute("autocapitalize", "off");
   field.setAttribute("spellcheck", "false");
 }
 // TEXTAREA INPUT STYLE
 function TextareaInput(cm) {
   this.cm = cm;
   // See input.poll and input.reset
   this.prevInput = "";
   // Flag that indicates whether we expect input to appear real soon
   // now (after some event like 'keypress' or 'input') and are
   // polling intensively.
   this.pollingFast = false;
   // Self-resetting timeout for the poller
   this.polling = new Delayed();
   // Tracks when input.reset has punted to just putting a short
   // string into the textarea instead of the full selection.
   this.inaccurateSelection = false;
   // Used to work around IE issue with selection being forgotten when focus moves away from textarea
   this.hasSelection = false;
   this.composing = null;
 };
 function hiddenTextarea() {
   var te = elt("textarea", null, null, "position: absolute; padding: 0; width: 1px; height: 1em; outline: none");
   var div = elt("div", [te], null, "overflow: hidden; position: relative; width: 3px; height: 0px;");
   // The textarea is kept positioned near the cursor to prevent the
   // fact that it'll be scrolled into view on input from scrolling
   // our fake cursor out of view. On webkit, when wrap=off, paste is
   // very slow. So make the area wide instead.
   if (webkit) te.style.width = "1000px";
   else te.setAttribute("wrap", "off");
   // If border: 0; -- iOS fails to open keyboard (issue #1287)
   if (ios) te.style.border = "1px solid black";
   disableBrowserMagic(te);
   return div;
 }
 TextareaInput.prototype = copyObj({
   init: function(display) {
     var input = this, cm = this.cm;
     // Wraps and hides input textarea
     var div = this.wrapper = hiddenTextarea();
     // The semihidden textarea that is focused when the editor is
     // focused, and receives input.
     var te = this.textarea = div.firstChild;
     display.wrapper.insertBefore(div, display.wrapper.firstChild);
     // Needed to hide big blue blinking cursor on Mobile Safari (doesn't seem to work in iOS 8 anymore)
     if (ios) te.style.width = "0px";
     on(te, "input", function() {
       if (ie && ie_version >= 9 && input.hasSelection) input.hasSelection = null;
       input.poll();
     });
     on(te, "paste", function(e) {
       if (handlePaste(e, cm)) return true;
       cm.state.pasteIncoming = true;
       input.fastPoll();
     });
     function prepareCopyCut(e) {
       if (cm.somethingSelected()) {
         lastCopied = cm.getSelections();
         if (input.inaccurateSelection) {
           input.prevInput = "";
           input.inaccurateSelection = false;
           te.value = lastCopied.join("\n");
           selectInput(te);
         }
       } else if (!cm.options.lineWiseCopyCut) {
         return;
       } else {
         var ranges = copyableRanges(cm);
         lastCopied = ranges.text;
         if (e.type == "cut") {
           cm.setSelections(ranges.ranges, null, sel_dontScroll);
         } else {
           input.prevInput = "";
           te.value = ranges.text.join("\n");
           selectInput(te);
         }
       }
       if (e.type == "cut") cm.state.cutIncoming = true;
     }
     on(te, "cut", prepareCopyCut);
     on(te, "copy", prepareCopyCut);
     on(display.scroller, "paste", function(e) {
       if (eventInWidget(display, e)) return;
       cm.state.pasteIncoming = true;
       input.focus();
     });
     // Prevent normal selection in the editor (we handle our own)
     on(display.lineSpace, "selectstart", function(e) {
       if (!eventInWidget(display, e)) e_preventDefault(e);
     });
     on(te, "compositionstart", function() {
       var start = cm.getCursor("from");
       input.composing = {
         start: start,
         range: cm.markText(start, cm.getCursor("to"), {className: "CodeMirror-composing"})
       };
     });
     on(te, "compositionend", function() {
       if (input.composing) {
         input.poll();
         input.composing.range.clear();
         input.composing = null;
       }
     });
   },
   prepareSelection: function() {
     // Redraw the selection and/or cursor
     var cm = this.cm, display = cm.display, doc = cm.doc;
     var result = prepareSelection(cm);
     // Move the hidden textarea near the cursor to prevent scrolling artifacts
     if (cm.options.moveInputWithCursor) {
       var headPos = cursorCoords(cm, doc.sel.primary().head, "div");
       var wrapOff = display.wrapper.getBoundingClientRect(), lineOff = display.lineDiv.getBoundingClientRect();
       result.teTop = Math.max(0, Math.min(display.wrapper.clientHeight - 10,
                                           headPos.top + lineOff.top - wrapOff.top));
       result.teLeft = Math.max(0, Math.min(display.wrapper.clientWidth - 10,
                                            headPos.left + lineOff.left - wrapOff.left));
     }
     return result;
   },
   showSelection: function(drawn) {
     var cm = this.cm, display = cm.display;
     removeChildrenAndAdd(display.cursorDiv, drawn.cursors);
     removeChildrenAndAdd(display.selectionDiv, drawn.selection);
     if (drawn.teTop != null) {
       this.wrapper.style.top = drawn.teTop + "px";
       this.wrapper.style.left = drawn.teLeft + "px";
     }
   },
   // Reset the input to correspond to the selection (or to be empty,
   // when not typing and nothing is selected)
   reset: function(typing) {
     if (this.contextMenuPending) return;
     var minimal, selected, cm = this.cm, doc = cm.doc;
     if (cm.somethingSelected()) {
       this.prevInput = "";
       var range = doc.sel.primary();
       minimal = hasCopyEvent &&
         (range.to().line - range.from().line > 100 || (selected = cm.getSelection()).length > 1000);
       var content = minimal ? "-" : selected || cm.getSelection();
       this.textarea.value = content;
       if (cm.state.focused) selectInput(this.textarea);
       if (ie && ie_version >= 9) this.hasSelection = content;
     } else if (!typing) {
       this.prevInput = this.textarea.value = "";
       if (ie && ie_version >= 9) this.hasSelection = null;
     }
     this.inaccurateSelection = minimal;
   },
   getField: function() { return this.textarea; },
   supportsTouch: function() { return false; },
   focus: function() {
     if (this.cm.options.readOnly != "nocursor" && (!mobile || activeElt() != this.textarea)) {
       try { this.textarea.focus(); }
       catch (e) {} // IE8 will throw if the textarea is display: none or not in DOM
     }
   },
   blur: function() { this.textarea.blur(); },
   resetPosition: function() {
     this.wrapper.style.top = this.wrapper.style.left = 0;
   },
   receivedFocus: function() { this.slowPoll(); },
   // Poll for input changes, using the normal rate of polling. This
   // runs as long as the editor is focused.
   slowPoll: function() {
     var input = this;
     if (input.pollingFast) return;
     input.polling.set(this.cm.options.pollInterval, function() {
       input.poll();
       if (input.cm.state.focused) input.slowPoll();
     });
   },
   // When an event has just come in that is likely to add or change
   // something in the input textarea, we poll faster, to ensure that
   // the change appears on the screen quickly.
   fastPoll: function() {
     var missed = false, input = this;
     input.pollingFast = true;
     function p() {
       var changed = input.poll();
       if (!changed && !missed) {missed = true; input.polling.set(60, p);}
       else {input.pollingFast = false; input.slowPoll();}
     }
     input.polling.set(20, p);
   },
   // Read input from the textarea, and update the document to match.
   // When something is selected, it is present in the textarea, and
   // selected (unless it is huge, in which case a placeholder is
   // used). When nothing is selected, the cursor sits after previously
   // seen text (can be empty), which is stored in prevInput (we must
   // not reset the textarea when typing, because that breaks IME).
   poll: function() {
     var cm = this.cm, input = this.textarea, prevInput = this.prevInput;
     // Since this is called a *lot*, try to bail out as cheaply as
     // possible when it is clear that nothing happened. hasSelection
     // will be the case when there is a lot of text in the textarea,
     // in which case reading its value would be expensive.
     if (this.contextMenuPending || !cm.state.focused ||
         (hasSelection(input) && !prevInput && !this.composing) ||
         isReadOnly(cm) || cm.options.disableInput || cm.state.keySeq)
       return false;
     var text = input.value;
     // If nothing changed, bail.
     if (text == prevInput && !cm.somethingSelected()) return false;
     // Work around nonsensical selection resetting in IE9/10, and
     // inexplicable appearance of private area unicode characters on
     // some key combos in Mac (#2689).
     if (ie && ie_version >= 9 && this.hasSelection === text ||
         mac && /[\uf700-\uf7ff]/.test(text)) {
       cm.display.input.reset();
       return false;
     }
     if (cm.doc.sel == cm.display.selForContextMenu) {
       var first = text.charCodeAt(0);
       if (first == 0x200b && !prevInput) prevInput = "\u200b";
       if (first == 0x21da) { this.reset(); return this.cm.execCommand("undo"); }
     }
     // Find the part of the input that is actually new
     var same = 0, l = Math.min(prevInput.length, text.length);
     while (same < l && prevInput.charCodeAt(same) == text.charCodeAt(same)) ++same;
     var self = this;
     runInOp(cm, function() {
       applyTextInput(cm, text.slice(same), prevInput.length - same,
                      null, self.composing ? "*compose" : null);
       // Don't leave long text in the textarea, since it makes further polling slow
       if (text.length > 1000 || text.indexOf("\n") > -1) input.value = self.prevInput = "";
       else self.prevInput = text;
       if (self.composing) {
         self.composing.range.clear();
         self.composing.range = cm.markText(self.composing.start, cm.getCursor("to"),
                                            {className: "CodeMirror-composing"});
       }
     });
     return true;
   },
   ensurePolled: function() {
     if (this.pollingFast && this.poll()) this.pollingFast = false;
   },
   onKeyPress: function() {
     if (ie && ie_version >= 9) this.hasSelection = null;
     this.fastPoll();
   },
   onContextMenu: function(e) {
     var input = this, cm = input.cm, display = cm.display, te = input.textarea;
     var pos = posFromMouse(cm, e), scrollPos = display.scroller.scrollTop;
     if (!pos || presto) return; // Opera is difficult.
     // Reset the current text selection only if the click is done outside of the selection
     // and 'resetSelectionOnContextMenu' option is true.
     var reset = cm.options.resetSelectionOnContextMenu;
     if (reset && cm.doc.sel.contains(pos) == -1)
       operation(cm, setSelection)(cm.doc, simpleSelection(pos), sel_dontScroll);
     var oldCSS = te.style.cssText;
     input.wrapper.style.position = "absolute";
     te.style.cssText = "position: fixed; width: 30px; height: 30px; top: " + (e.clientY - 5) +
       "px; left: " + (e.clientX - 5) + "px; z-index: 1000; background: " +
       (ie ? "rgba(255, 255, 255, .05)" : "transparent") +
       "; outline: none; border-width: 0; outline: none; overflow: hidden; opacity: .05; filter: alpha(opacity=5);";
     if (webkit) var oldScrollY = window.scrollY; // Work around Chrome issue (#2712)
     display.input.focus();
     if (webkit) window.scrollTo(null, oldScrollY);
     display.input.reset();
     // Adds "Select all" to context menu in FF
     if (!cm.somethingSelected()) te.value = input.prevInput = " ";
     input.contextMenuPending = true;
     display.selForContextMenu = cm.doc.sel;
     clearTimeout(display.detectingSelectAll);
     // Select-all will be greyed out if there's nothing to select, so
     // this adds a zero-width space so that we can later check whether
     // it got selected.
     function prepareSelectAllHack() {
       if (te.selectionStart != null) {
         var selected = cm.somethingSelected();
         var extval = "\u200b" + (selected ? te.value : "");
         te.value = "\u21da"; // Used to catch context-menu undo
         te.value = extval;
         input.prevInput = selected ? "" : "\u200b";
         te.selectionStart = 1; te.selectionEnd = extval.length;
         // Re-set this, in case some other handler touched the
         // selection in the meantime.
         display.selForContextMenu = cm.doc.sel;
       }
     }
     function rehide() {
       input.contextMenuPending = false;
       input.wrapper.style.position = "relative";
       te.style.cssText = oldCSS;
       if (ie && ie_version < 9) display.scrollbars.setScrollTop(display.scroller.scrollTop = scrollPos);
       // Try to detect the user choosing select-all
       if (te.selectionStart != null) {
         if (!ie || (ie && ie_version < 9)) prepareSelectAllHack();
         var i = 0, poll = function() {
           if (display.selForContextMenu == cm.doc.sel && te.selectionStart == 0 &&
               te.selectionEnd > 0 && input.prevInput == "\u200b")
             operation(cm, commands.selectAll)(cm);
           else if (i++ < 10) display.detectingSelectAll = setTimeout(poll, 500);
           else display.input.reset();
         };
         display.detectingSelectAll = setTimeout(poll, 200);
       }
     }
     if (ie && ie_version >= 9) prepareSelectAllHack();
     if (captureRightClick) {
       e_stop(e);
       var mouseup = function() {
         off(window, "mouseup", mouseup);
         setTimeout(rehide, 20);
       };
       on(window, "mouseup", mouseup);
     } else {
       setTimeout(rehide, 50);
     }
   },
   setUneditable: nothing,
   needsContentAttribute: false
 }, TextareaInput.prototype);
 // CONTENTEDITABLE INPUT STYLE
 function ContentEditableInput(cm) {
   this.cm = cm;
   this.lastAnchorNode = this.lastAnchorOffset = this.lastFocusNode = this.lastFocusOffset = null;
   this.polling = new Delayed();
   this.gracePeriod = false;
 }
 ContentEditableInput.prototype = copyObj({
   init: function(display) {
     var input = this, cm = input.cm;
     var div = input.div = display.lineDiv;
     div.contentEditable = "true";
     disableBrowserMagic(div);
     on(div, "paste", function(e) { handlePaste(e, cm); })
     on(div, "compositionstart", function(e) {
       var data = e.data;
       input.composing = {sel: cm.doc.sel, data: data, startData: data};
       if (!data) return;
       var prim = cm.doc.sel.primary();
       var line = cm.getLine(prim.head.line);
       var found = line.indexOf(data, Math.max(0, prim.head.ch - data.length));
       if (found > -1 && found <= prim.head.ch)
         input.composing.sel = simpleSelection(Pos(prim.head.line, found),
                                               Pos(prim.head.line, found + data.length));
     });
     on(div, "compositionupdate", function(e) {
       input.composing.data = e.data;
     });
     on(div, "compositionend", function(e) {
       var ours = input.composing;
       if (!ours) return;
       if (e.data != ours.startData && !/\u200b/.test(e.data))
         ours.data = e.data;
       // Need a small delay to prevent other code (input event,
       // selection polling) from doing damage when fired right after
       // compositionend.
       setTimeout(function() {
         if (!ours.handled)
           input.applyComposition(ours);
         if (input.composing == ours)
           input.composing = null;
       }, 50);
     });
     on(div, "touchstart", function() {
       input.forceCompositionEnd();
     });
     on(div, "input", function() {
       if (input.composing) return;
       if (!input.pollContent())
         runInOp(input.cm, function() {regChange(cm);});
     });
     function onCopyCut(e) {
       if (cm.somethingSelected()) {
         lastCopied = cm.getSelections();
         if (e.type == "cut") cm.replaceSelection("", null, "cut");
       } else if (!cm.options.lineWiseCopyCut) {
         return;
       } else {
         var ranges = copyableRanges(cm);
         lastCopied = ranges.text;
         if (e.type == "cut") {
           cm.operation(function() {
             cm.setSelections(ranges.ranges, 0, sel_dontScroll);
             cm.replaceSelection("", null, "cut");
           });
         }
       }
       // iOS exposes the clipboard API, but seems to discard content inserted into it
       if (e.clipboardData && !ios) {
         e.preventDefault();
         e.clipboardData.clearData();
         e.clipboardData.setData("text/plain", lastCopied.join("\n"));
       } else {
         // Old-fashioned briefly-focus-a-textarea hack
         var kludge = hiddenTextarea(), te = kludge.firstChild;
         cm.display.lineSpace.insertBefore(kludge, cm.display.lineSpace.firstChild);
         te.value = lastCopied.join("\n");
         var hadFocus = document.activeElement;
         selectInput(te);
         setTimeout(function() {
           cm.display.lineSpace.removeChild(kludge);
           hadFocus.focus();
         }, 50);
       }
     }
     on(div, "copy", onCopyCut);
     on(div, "cut", onCopyCut);
   },
   prepareSelection: function() {
     var result = prepareSelection(this.cm, false);
     result.focus = this.cm.state.focused;
     return result;
   },
   showSelection: function(info) {
     if (!info || !this.cm.display.view.length) return;
     if (info.focus) this.showPrimarySelection();
     this.showMultipleSelections(info);
   },
   showPrimarySelection: function() {
     var sel = window.getSelection(), prim = this.cm.doc.sel.primary();
     var curAnchor = domToPos(this.cm, sel.anchorNode, sel.anchorOffset);
     var curFocus = domToPos(this.cm, sel.focusNode, sel.focusOffset);
     if (curAnchor && !curAnchor.bad && curFocus && !curFocus.bad &&
         cmp(minPos(curAnchor, curFocus), prim.from()) == 0 &&
         cmp(maxPos(curAnchor, curFocus), prim.to()) == 0)
       return;
     var start = posToDOM(this.cm, prim.from());
     var end = posToDOM(this.cm, prim.to());
     if (!start && !end) return;
     var view = this.cm.display.view;
     var old = sel.rangeCount && sel.getRangeAt(0);
     if (!start) {
       start = {node: view[0].measure.map[2], offset: 0};
     } else if (!end) { // FIXME dangerously hacky
       var measure = view[view.length - 1].measure;
       var map = measure.maps ? measure.maps[measure.maps.length - 1] : measure.map;
       end = {node: map[map.length - 1], offset: map[map.length - 2] - map[map.length - 3]};
     }
     try { var rng = range(start.node, start.offset, end.offset, end.node); }
     catch(e) {} // Our model of the DOM might be outdated, in which case the range we try to set can be impossible
     if (rng) {
       sel.removeAllRanges();
       sel.addRange(rng);
       if (old && sel.anchorNode == null) sel.addRange(old);
       else if (gecko) this.startGracePeriod();
     }
     this.rememberSelection();
   },
   startGracePeriod: function() {
     var input = this;
     clearTimeout(this.gracePeriod);
     this.gracePeriod = setTimeout(function() {
       input.gracePeriod = false;
       if (input.selectionChanged())
         input.cm.operation(function() { input.cm.curOp.selectionChanged = true; });
     }, 20);
   },
   showMultipleSelections: function(info) {
     removeChildrenAndAdd(this.cm.display.cursorDiv, info.cursors);
     removeChildrenAndAdd(this.cm.display.selectionDiv, info.selection);
   },
   rememberSelection: function() {
     var sel = window.getSelection();
     this.lastAnchorNode = sel.anchorNode; this.lastAnchorOffset = sel.anchorOffset;
     this.lastFocusNode = sel.focusNode; this.lastFocusOffset = sel.focusOffset;
   },
   selectionInEditor: function() {
     var sel = window.getSelection();
     if (!sel.rangeCount) return false;
     var node = sel.getRangeAt(0).commonAncestorContainer;
     return contains(this.div, node);
   },
   focus: function() {
     if (this.cm.options.readOnly != "nocursor") this.div.focus();
   },
   blur: function() { this.div.blur(); },
   getField: function() { return this.div; },
   supportsTouch: function() { return true; },
   receivedFocus: function() {
     var input = this;
     if (this.selectionInEditor())
       this.pollSelection();
     else
       runInOp(this.cm, function() { input.cm.curOp.selectionChanged = true; });
     function poll() {
       if (input.cm.state.focused) {
         input.pollSelection();
         input.polling.set(input.cm.options.pollInterval, poll);
       }
     }
     this.polling.set(this.cm.options.pollInterval, poll);
   },
   selectionChanged: function() {
     var sel = window.getSelection();
     return sel.anchorNode != this.lastAnchorNode || sel.anchorOffset != this.lastAnchorOffset ||
       sel.focusNode != this.lastFocusNode || sel.focusOffset != this.lastFocusOffset;
   },
   pollSelection: function() {
     if (!this.composing && !this.gracePeriod && this.selectionChanged()) {
       var sel = window.getSelection(), cm = this.cm;
       this.rememberSelection();
       var anchor = domToPos(cm, sel.anchorNode, sel.anchorOffset);
       var head = domToPos(cm, sel.focusNode, sel.focusOffset);
       if (anchor && head) runInOp(cm, function() {
         setSelection(cm.doc, simpleSelection(anchor, head), sel_dontScroll);
         if (anchor.bad || head.bad) cm.curOp.selectionChanged = true;
       });
     }
   },
   pollContent: function() {
     var cm = this.cm, display = cm.display, sel = cm.doc.sel.primary();
     var from = sel.from(), to = sel.to();
     if (from.line < display.viewFrom || to.line > display.viewTo - 1) return false;
     var fromIndex;
     if (from.line == display.viewFrom || (fromIndex = findViewIndex(cm, from.line)) == 0) {
       var fromLine = lineNo(display.view[0].line);
       var fromNode = display.view[0].node;
     } else {
       var fromLine = lineNo(display.view[fromIndex].line);
       var fromNode = display.view[fromIndex - 1].node.nextSibling;
     }
     var toIndex = findViewIndex(cm, to.line);
     if (toIndex == display.view.length - 1) {
       var toLine = display.viewTo - 1;
       var toNode = display.lineDiv.lastChild;
     } else {
       var toLine = lineNo(display.view[toIndex + 1].line) - 1;
       var toNode = display.view[toIndex + 1].node.previousSibling;
     }
     var newText = cm.doc.splitLines(domTextBetween(cm, fromNode, toNode, fromLine, toLine));
     var oldText = getBetween(cm.doc, Pos(fromLine, 0), Pos(toLine, getLine(cm.doc, toLine).text.length));
     while (newText.length > 1 && oldText.length > 1) {
       if (lst(newText) == lst(oldText)) { newText.pop(); oldText.pop(); toLine--; }
       else if (newText[0] == oldText[0]) { newText.shift(); oldText.shift(); fromLine++; }
       else break;
     }
     var cutFront = 0, cutEnd = 0;
     var newTop = newText[0], oldTop = oldText[0], maxCutFront = Math.min(newTop.length, oldTop.length);
     while (cutFront < maxCutFront && newTop.charCodeAt(cutFront) == oldTop.charCodeAt(cutFront))
       ++cutFront;
     var newBot = lst(newText), oldBot = lst(oldText);
     var maxCutEnd = Math.min(newBot.length - (newText.length == 1 ? cutFront : 0),
                              oldBot.length - (oldText.length == 1 ? cutFront : 0));
     while (cutEnd < maxCutEnd &&
            newBot.charCodeAt(newBot.length - cutEnd - 1) == oldBot.charCodeAt(oldBot.length - cutEnd - 1))
       ++cutEnd;
     newText[newText.length - 1] = newBot.slice(0, newBot.length - cutEnd);
     newText[0] = newText[0].slice(cutFront);
     var chFrom = Pos(fromLine, cutFront);
     var chTo = Pos(toLine, oldText.length ? lst(oldText).length - cutEnd : 0);
     if (newText.length > 1 || newText[0] || cmp(chFrom, chTo)) {
       replaceRange(cm.doc, newText, chFrom, chTo, "+input");
       return true;
     }
   },
   ensurePolled: function() {
     this.forceCompositionEnd();
   },
   reset: function() {
     this.forceCompositionEnd();
   },
   forceCompositionEnd: function() {
     if (!this.composing || this.composing.handled) return;
     this.applyComposition(this.composing);
     this.composing.handled = true;
     this.div.blur();
     this.div.focus();
   },
   applyComposition: function(composing) {
     if (composing.data && composing.data != composing.startData)
       operation(this.cm, applyTextInput)(this.cm, composing.data, 0, composing.sel);
   },
   setUneditable: function(node) {
     node.setAttribute("contenteditable", "false");
   },
   onKeyPress: function(e) {
     e.preventDefault();
     operation(this.cm, applyTextInput)(this.cm, String.fromCharCode(e.charCode == null ? e.keyCode : e.charCode), 0);
   },
   onContextMenu: nothing,
   resetPosition: nothing,
   needsContentAttribute: true
 }, ContentEditableInput.prototype);
 function posToDOM(cm, pos) {
   var view = findViewForLine(cm, pos.line);
   if (!view || view.hidden) return null;
   var line = getLine(cm.doc, pos.line);
   var info = mapFromLineView(view, line, pos.line);
   var order = getOrder(line), side = "left";
   if (order) {
     var partPos = getBidiPartAt(order, pos.ch);
     side = partPos % 2 ? "right" : "left";
   }
   var result = nodeAndOffsetInLineMap(info.map, pos.ch, side);
   result.offset = result.collapse == "right" ? result.end : result.start;
   return result;
 }
 function badPos(pos, bad) { if (bad) pos.bad = true; return pos; }
 function domToPos(cm, node, offset) {
   var lineNode;
   if (node == cm.display.lineDiv) {
     lineNode = cm.display.lineDiv.childNodes[offset];
     if (!lineNode) return badPos(cm.clipPos(Pos(cm.display.viewTo - 1)), true);
     node = null; offset = 0;
   } else {
     for (lineNode = node;; lineNode = lineNode.parentNode) {
       if (!lineNode || lineNode == cm.display.lineDiv) return null;
       if (lineNode.parentNode && lineNode.parentNode == cm.display.lineDiv) break;
     }
   }
   for (var i = 0; i < cm.display.view.length; i++) {
     var lineView = cm.display.view[i];
     if (lineView.node == lineNode)
       return locateNodeInLineView(lineView, node, offset);
   }
 }
 function locateNodeInLineView(lineView, node, offset) {
   var wrapper = lineView.text.firstChild, bad = false;
   if (!node || !contains(wrapper, node)) return badPos(Pos(lineNo(lineView.line), 0), true);
   if (node == wrapper) {
     bad = true;
     node = wrapper.childNodes[offset];
     offset = 0;
     if (!node) {
       var line = lineView.rest ? lst(lineView.rest) : lineView.line;
       return badPos(Pos(lineNo(line), line.text.length), bad);
     }
   }
   var textNode = node.nodeType == 3 ? node : null, topNode = node;
   if (!textNode && node.childNodes.length == 1 && node.firstChild.nodeType == 3) {
     textNode = node.firstChild;
     if (offset) offset = textNode.nodeValue.length;
   }
   while (topNode.parentNode != wrapper) topNode = topNode.parentNode;
   var measure = lineView.measure, maps = measure.maps;
   function find(textNode, topNode, offset) {
     for (var i = -1; i < (maps ? maps.length : 0); i++) {
       var map = i < 0 ? measure.map : maps[i];
       for (var j = 0; j < map.length; j += 3) {
         var curNode = map[j + 2];
         if (curNode == textNode || curNode == topNode) {
           var line = lineNo(i < 0 ? lineView.line : lineView.rest[i]);
           var ch = map[j] + offset;
           if (offset < 0 || curNode != textNode) ch = map[j + (offset ? 1 : 0)];
           return Pos(line, ch);
         }
       }
     }
   }
   var found = find(textNode, topNode, offset);
   if (found) return badPos(found, bad);
   // FIXME this is all really shaky. might handle the few cases it needs to handle, but likely to cause problems
   for (var after = topNode.nextSibling, dist = textNode ? textNode.nodeValue.length - offset : 0; after; after = after.nextSibling) {
     found = find(after, after.firstChild, 0);
     if (found)
       return badPos(Pos(found.line, found.ch - dist), bad);
     else
       dist += after.textContent.length;
   }
   for (var before = topNode.previousSibling, dist = offset; before; before = before.previousSibling) {
     found = find(before, before.firstChild, -1);
     if (found)
       return badPos(Pos(found.line, found.ch + dist), bad);
     else
       dist += after.textContent.length;
   }
 }
 function domTextBetween(cm, from, to, fromLine, toLine) {
   var text = "", closing = false, lineSep = cm.doc.lineSeparator();
   function recognizeMarker(id) { return function(marker) { return marker.id == id; }; }
   function walk(node) {
     if (node.nodeType == 1) {
       var cmText = node.getAttribute("cm-text");
       if (cmText != null) {
         if (cmText == "") cmText = node.textContent.replace(/\u200b/g, "");
         text += cmText;
         return;
       }
       var markerID = node.getAttribute("cm-marker"), range;
       if (markerID) {
         var found = cm.findMarks(Pos(fromLine, 0), Pos(toLine + 1, 0), recognizeMarker(+markerID));
         if (found.length && (range = found[0].find()))
           text += getBetween(cm.doc, range.from, range.to).join(lineSep);
         return;
       }
       if (node.getAttribute("contenteditable") == "false") return;
       for (var i = 0; i < node.childNodes.length; i++)
         walk(node.childNodes[i]);
       if (/^(pre|div|p)$/i.test(node.nodeName))
         closing = true;
     } else if (node.nodeType == 3) {
       var val = node.nodeValue;
       if (!val) return;
       if (closing) {
         text += lineSep;
         closing = false;
       }
       text += val;
     }
   }
   for (;;) {
     walk(from);
     if (from == to) break;
     from = from.nextSibling;
   }
   return text;
 }
 CodeMirror.inputStyles = {"textarea": TextareaInput, "contenteditable": ContentEditableInput};
 // SELECTION / CURSOR
 // Selection objects are immutable. A new one is created every time
 // the selection changes. A selection is one or more non-overlapping
 // (and non-touching) ranges, sorted, and an integer that indicates
 // which one is the primary selection (the one that's scrolled into
 // view, that getCursor returns, etc).
 function Selection(ranges, primIndex) {
   this.ranges = ranges;
   this.primIndex = primIndex;
 }
 Selection.prototype = {
   primary: function() { return this.ranges[this.primIndex]; },
   equals: function(other) {
     if (other == this) return true;
     if (other.primIndex != this.primIndex || other.ranges.length != this.ranges.length) return false;
     for (var i = 0; i < this.ranges.length; i++) {
       var here = this.ranges[i], there = other.ranges[i];
       if (cmp(here.anchor, there.anchor) != 0 || cmp(here.head, there.head) != 0) return false;
     }
     return true;
   },
   deepCopy: function() {
     for (var out = [], i = 0; i < this.ranges.length; i++)
       out[i] = new Range(copyPos(this.ranges[i].anchor), copyPos(this.ranges[i].head));
     return new Selection(out, this.primIndex);
   },
   somethingSelected: function() {
     for (var i = 0; i < this.ranges.length; i++)
       if (!this.ranges[i].empty()) return true;
     return false;
   },
   contains: function(pos, end) {
     if (!end) end = pos;
     for (var i = 0; i < this.ranges.length; i++) {
       var range = this.ranges[i];
       if (cmp(end, range.from()) >= 0 && cmp(pos, range.to()) <= 0)
         return i;
     }
     return -1;
   }
 };
 function Range(anchor, head) {
   this.anchor = anchor; this.head = head;
 }
 Range.prototype = {
   from: function() { return minPos(this.anchor, this.head); },
   to: function() { return maxPos(this.anchor, this.head); },
   empty: function() {
     return this.head.line == this.anchor.line && this.head.ch == this.anchor.ch;
   }
 };
 // Take an unsorted, potentially overlapping set of ranges, and
 // build a selection out of it. 'Consumes' ranges array (modifying
 // it).
 function normalizeSelection(ranges, primIndex) {
   var prim = ranges[primIndex];
   ranges.sort(function(a, b) { return cmp(a.from(), b.from()); });
   primIndex = indexOf(ranges, prim);
   for (var i = 1; i < ranges.length; i++) {
     var cur = ranges[i], prev = ranges[i - 1];
     if (cmp(prev.to(), cur.from()) >= 0) {
       var from = minPos(prev.from(), cur.from()), to = maxPos(prev.to(), cur.to());
       var inv = prev.empty() ? cur.from() == cur.head : prev.from() == prev.head;
       if (i <= primIndex) --primIndex;
       ranges.splice(--i, 2, new Range(inv ? to : from, inv ? from : to));
     }
   }
   return new Selection(ranges, primIndex);
 }
 function simpleSelection(anchor, head) {
   return new Selection([new Range(anchor, head || anchor)], 0);
 }
 // Most of the external API clips given positions to make sure they
 // actually exist within the document.
 function clipLine(doc, n) {return Math.max(doc.first, Math.min(n, doc.first + doc.size - 1));}
 function clipPos(doc, pos) {
   if (pos.line < doc.first) return Pos(doc.first, 0);
   var last = doc.first + doc.size - 1;
   if (pos.line > last) return Pos(last, getLine(doc, last).text.length);
   return clipToLen(pos, getLine(doc, pos.line).text.length);
 }
 function clipToLen(pos, linelen) {
   var ch = pos.ch;
   if (ch == null || ch > linelen) return Pos(pos.line, linelen);
   else if (ch < 0) return Pos(pos.line, 0);
   else return pos;
 }
 function isLine(doc, l) {return l >= doc.first && l < doc.first + doc.size;}
 function clipPosArray(doc, array) {
   for (var out = [], i = 0; i < array.length; i++) out[i] = clipPos(doc, array[i]);
   return out;
 }
 // SELECTION UPDATES
 // The 'scroll' parameter given to many of these indicated whether
 // the new cursor position should be scrolled into view after
 // modifying the selection.
 // If shift is held or the extend flag is set, extends a range to
 // include a given position (and optionally a second position).
 // Otherwise, simply returns the range between the given positions.
 // Used for cursor motion and such.
 function extendRange(doc, range, head, other) {
   if (doc.cm && doc.cm.display.shift || doc.extend) {
     var anchor = range.anchor;
     if (other) {
       var posBefore = cmp(head, anchor) < 0;
       if (posBefore != (cmp(other, anchor) < 0)) {
         anchor = head;
         head = other;
       } else if (posBefore != (cmp(head, other) < 0)) {
         head = other;
       }
     }
     return new Range(anchor, head);
   } else {
     return new Range(other || head, head);
   }
 }
 // Extend the primary selection range, discard the rest.
 function extendSelection(doc, head, other, options) {
   setSelection(doc, new Selection([extendRange(doc, doc.sel.primary(), head, other)], 0), options);
 }
 // Extend all selections (pos is an array of selections with length
 // equal the number of selections)
 function extendSelections(doc, heads, options) {
   for (var out = [], i = 0; i < doc.sel.ranges.length; i++)
     out[i] = extendRange(doc, doc.sel.ranges[i], heads[i], null);
   var newSel = normalizeSelection(out, doc.sel.primIndex);
   setSelection(doc, newSel, options);
 }
 // Updates a single range in the selection.
 function replaceOneSelection(doc, i, range, options) {
   var ranges = doc.sel.ranges.slice(0);
   ranges[i] = range;
   setSelection(doc, normalizeSelection(ranges, doc.sel.primIndex), options);
 }
 // Reset the selection to a single range.
 function setSimpleSelection(doc, anchor, head, options) {
   setSelection(doc, simpleSelection(anchor, head), options);
 }
 // Give beforeSelectionChange handlers a change to influence a
 // selection update.
 function filterSelectionChange(doc, sel) {
   var obj = {
     ranges: sel.ranges,
     update: function(ranges) {
       this.ranges = [];
       for (var i = 0; i < ranges.length; i++)
         this.ranges[i] = new Range(clipPos(doc, ranges[i].anchor),
                                    clipPos(doc, ranges[i].head));
     }
   };
   signal(doc, "beforeSelectionChange", doc, obj);
   if (doc.cm) signal(doc.cm, "beforeSelectionChange", doc.cm, obj);
   if (obj.ranges != sel.ranges) return normalizeSelection(obj.ranges, obj.ranges.length - 1);
   else return sel;
 }
 function setSelectionReplaceHistory(doc, sel, options) {
   var done = doc.history.done, last = lst(done);
   if (last && last.ranges) {
     done[done.length - 1] = sel;
     setSelectionNoUndo(doc, sel, options);
   } else {
     setSelection(doc, sel, options);
   }
 }
 // Set a new selection.
 function setSelection(doc, sel, options) {
   setSelectionNoUndo(doc, sel, options);
   addSelectionToHistory(doc, doc.sel, doc.cm ? doc.cm.curOp.id : NaN, options);
 }
 function setSelectionNoUndo(doc, sel, options) {
   if (hasHandler(doc, "beforeSelectionChange") || doc.cm && hasHandler(doc.cm, "beforeSelectionChange"))
     sel = filterSelectionChange(doc, sel);
   var bias = options && options.bias ||
     (cmp(sel.primary().head, doc.sel.primary().head) < 0 ? -1 : 1);
   setSelectionInner(doc, skipAtomicInSelection(doc, sel, bias, true));
   if (!(options && options.scroll === false) && doc.cm)
     ensureCursorVisible(doc.cm);
 }
 function setSelectionInner(doc, sel) {
   if (sel.equals(doc.sel)) return;
   doc.sel = sel;
   if (doc.cm) {
     doc.cm.curOp.updateInput = doc.cm.curOp.selectionChanged = true;
     signalCursorActivity(doc.cm);
   }
   signalLater(doc, "cursorActivity", doc);
 }
 // Verify that the selection does not partially select any atomic
 // marked ranges.
 function reCheckSelection(doc) {
   setSelectionInner(doc, skipAtomicInSelection(doc, doc.sel, null, false), sel_dontScroll);
 }
 // Return a selection that does not partially select any atomic
 // ranges.
 function skipAtomicInSelection(doc, sel, bias, mayClear) {
   var out;
   for (var i = 0; i < sel.ranges.length; i++) {
     var range = sel.ranges[i];
     var newAnchor = skipAtomic(doc, range.anchor, bias, mayClear);
     var newHead = skipAtomic(doc, range.head, bias, mayClear);
     if (out || newAnchor != range.anchor || newHead != range.head) {
       if (!out) out = sel.ranges.slice(0, i);
       out[i] = new Range(newAnchor, newHead);
     }
   }
   return out ? normalizeSelection(out, sel.primIndex) : sel;
 }
 // Ensure a given position is not inside an atomic range.
 function skipAtomic(doc, pos, bias, mayClear) {
   var flipped = false, curPos = pos;
   var dir = bias || 1;
   doc.cantEdit = false;
   search: for (;;) {
     var line = getLine(doc, curPos.line);
     if (line.markedSpans) {
       for (var i = 0; i < line.markedSpans.length; ++i) {
         var sp = line.markedSpans[i], m = sp.marker;
         if ((sp.from == null || (m.inclusiveLeft ? sp.from <= curPos.ch : sp.from < curPos.ch)) &&
             (sp.to == null || (m.inclusiveRight ? sp.to >= curPos.ch : sp.to > curPos.ch))) {
           if (mayClear) {
             signal(m, "beforeCursorEnter");
             if (m.explicitlyCleared) {
               if (!line.markedSpans) break;
               else {--i; continue;}
             }
           }
           if (!m.atomic) continue;
           var newPos = m.find(dir < 0 ? -1 : 1);
           if (cmp(newPos, curPos) == 0) {
             newPos.ch += dir;
             if (newPos.ch < 0) {
               if (newPos.line > doc.first) newPos = clipPos(doc, Pos(newPos.line - 1));
               else newPos = null;
             } else if (newPos.ch > line.text.length) {
               if (newPos.line < doc.first + doc.size - 1) newPos = Pos(newPos.line + 1, 0);
               else newPos = null;
             }
             if (!newPos) {
               if (flipped) {
                 // Driven in a corner -- no valid cursor position found at all
                 // -- try again *with* clearing, if we didn't already
                 if (!mayClear) return skipAtomic(doc, pos, bias, true);
                 // Otherwise, turn off editing until further notice, and return the start of the doc
                 doc.cantEdit = true;
                 return Pos(doc.first, 0);
               }
               flipped = true; newPos = pos; dir = -dir;
             }
           }
           curPos = newPos;
           continue search;
         }
       }
     }
     return curPos;
   }
 }
 // SELECTION DRAWING
 function updateSelection(cm) {
   cm.display.input.showSelection(cm.display.input.prepareSelection());
 }
 function prepareSelection(cm, primary) {
   var doc = cm.doc, result = {};
   var curFragment = result.cursors = document.createDocumentFragment();
   var selFragment = result.selection = document.createDocumentFragment();
   for (var i = 0; i < doc.sel.ranges.length; i++) {
     if (primary === false && i == doc.sel.primIndex) continue;
     var range = doc.sel.ranges[i];
     var collapsed = range.empty();
     if (collapsed || cm.options.showCursorWhenSelecting)
       drawSelectionCursor(cm, range.head, curFragment);
     if (!collapsed)
       drawSelectionRange(cm, range, selFragment);
   }
   return result;
 }
 // Draws a cursor for the given range
 function drawSelectionCursor(cm, head, output) {
   var pos = cursorCoords(cm, head, "div", null, null, !cm.options.singleCursorHeightPerLine);
   var cursor = output.appendChild(elt("div", "\u00a0", "CodeMirror-cursor"));
   cursor.style.left = pos.left + "px";
   cursor.style.top = pos.top + "px";
   cursor.style.height = Math.max(0, pos.bottom - pos.top) * cm.options.cursorHeight + "px";
   if (pos.other) {
     // Secondary cursor, shown when on a 'jump' in bi-directional text
     var otherCursor = output.appendChild(elt("div", "\u00a0", "CodeMirror-cursor CodeMirror-secondarycursor"));
     otherCursor.style.display = "";
     otherCursor.style.left = pos.other.left + "px";
     otherCursor.style.top = pos.other.top + "px";
     otherCursor.style.height = (pos.other.bottom - pos.other.top) * .85 + "px";
   }
 }
 // Draws the given range as a highlighted selection
 function drawSelectionRange(cm, range, output) {
   var display = cm.display, doc = cm.doc;
   var fragment = document.createDocumentFragment();
   var padding = paddingH(cm.display), leftSide = padding.left;
   var rightSide = Math.max(display.sizerWidth, displayWidth(cm) - display.sizer.offsetLeft) - padding.right;
   function add(left, top, width, bottom) {
     if (top < 0) top = 0;
     top = Math.round(top);
     bottom = Math.round(bottom);
     fragment.appendChild(elt("div", null, "CodeMirror-selected", "position: absolute; left: " + left +
                              "px; top: " + top + "px; width: " + (width == null ? rightSide - left : width) +
                              "px; height: " + (bottom - top) + "px"));
   }
   function drawForLine(line, fromArg, toArg) {
     var lineObj = getLine(doc, line);
     var lineLen = lineObj.text.length;
     var start, end;
     function coords(ch, bias) {
       return charCoords(cm, Pos(line, ch), "div", lineObj, bias);
     }
     iterateBidiSections(getOrder(lineObj), fromArg || 0, toArg == null ? lineLen : toArg, function(from, to, dir) {
       var leftPos = coords(from, "left"), rightPos, left, right;
       if (from == to) {
         rightPos = leftPos;
         left = right = leftPos.left;
       } else {
         rightPos = coords(to - 1, "right");
         if (dir == "rtl") { var tmp = leftPos; leftPos = rightPos; rightPos = tmp; }
         left = leftPos.left;
         right = rightPos.right;
       }
       if (fromArg == null && from == 0) left = leftSide;
       if (rightPos.top - leftPos.top > 3) { // Different lines, draw top part
         add(left, leftPos.top, null, leftPos.bottom);
         left = leftSide;
         if (leftPos.bottom < rightPos.top) add(left, leftPos.bottom, null, rightPos.top);
       }
       if (toArg == null && to == lineLen) right = rightSide;
       if (!start || leftPos.top < start.top || leftPos.top == start.top && leftPos.left < start.left)
         start = leftPos;
       if (!end || rightPos.bottom > end.bottom || rightPos.bottom == end.bottom && rightPos.right > end.right)
         end = rightPos;
       if (left < leftSide + 1) left = leftSide;
       add(left, rightPos.top, right - left, rightPos.bottom);
     });
     return {start: start, end: end};
   }
   var sFrom = range.from(), sTo = range.to();
   if (sFrom.line == sTo.line) {
     drawForLine(sFrom.line, sFrom.ch, sTo.ch);
   } else {
     var fromLine = getLine(doc, sFrom.line), toLine = getLine(doc, sTo.line);
     var singleVLine = visualLine(fromLine) == visualLine(toLine);
     var leftEnd = drawForLine(sFrom.line, sFrom.ch, singleVLine ? fromLine.text.length + 1 : null).end;
     var rightStart = drawForLine(sTo.line, singleVLine ? 0 : null, sTo.ch).start;
     if (singleVLine) {
       if (leftEnd.top < rightStart.top - 2) {
         add(leftEnd.right, leftEnd.top, null, leftEnd.bottom);
         add(leftSide, rightStart.top, rightStart.left, rightStart.bottom);
       } else {
         add(leftEnd.right, leftEnd.top, rightStart.left - leftEnd.right, leftEnd.bottom);
       }
     }
     if (leftEnd.bottom < rightStart.top)
       add(leftSide, leftEnd.bottom, null, rightStart.top);
   }
   output.appendChild(fragment);
 }
 // Cursor-blinking
 function restartBlink(cm) {
   if (!cm.state.focused) return;
   var display = cm.display;
   clearInterval(display.blinker);
   var on = true;
   display.cursorDiv.style.visibility = "";
   if (cm.options.cursorBlinkRate > 0)
     display.blinker = setInterval(function() {
       display.cursorDiv.style.visibility = (on = !on) ? "" : "hidden";
     }, cm.options.cursorBlinkRate);
   else if (cm.options.cursorBlinkRate < 0)
     display.cursorDiv.style.visibility = "hidden";
 }
 // HIGHLIGHT WORKER
 function startWorker(cm, time) {
   if (cm.doc.mode.startState && cm.doc.frontier < cm.display.viewTo)
     cm.state.highlight.set(time, bind(highlightWorker, cm));
 }
 function highlightWorker(cm) {
   var doc = cm.doc;
   if (doc.frontier < doc.first) doc.frontier = doc.first;
   if (doc.frontier >= cm.display.viewTo) return;
   var end = +new Date + cm.options.workTime;
   var state = copyState(doc.mode, getStateBefore(cm, doc.frontier));
   var changedLines = [];
   doc.iter(doc.frontier, Math.min(doc.first + doc.size, cm.display.viewTo + 500), function(line) {
     if (doc.frontier >= cm.display.viewFrom) { // Visible
       var oldStyles = line.styles, tooLong = line.text.length > cm.options.maxHighlightLength;
       var highlighted = highlightLine(cm, line, tooLong ? copyState(doc.mode, state) : state, true);
       line.styles = highlighted.styles;
       var oldCls = line.styleClasses, newCls = highlighted.classes;
       if (newCls) line.styleClasses = newCls;
       else if (oldCls) line.styleClasses = null;
       var ischange = !oldStyles || oldStyles.length != line.styles.length ||
         oldCls != newCls && (!oldCls || !newCls || oldCls.bgClass != newCls.bgClass || oldCls.textClass != newCls.textClass);
       for (var i = 0; !ischange && i < oldStyles.length; ++i) ischange = oldStyles[i] != line.styles[i];
       if (ischange) changedLines.push(doc.frontier);
       line.stateAfter = tooLong ? state : copyState(doc.mode, state);
     } else {
       if (line.text.length <= cm.options.maxHighlightLength)
         processLine(cm, line.text, state);
       line.stateAfter = doc.frontier % 5 == 0 ? copyState(doc.mode, state) : null;
     }
     ++doc.frontier;
     if (+new Date > end) {
       startWorker(cm, cm.options.workDelay);
       return true;
     }
   });
   if (changedLines.length) runInOp(cm, function() {
     for (var i = 0; i < changedLines.length; i++)
       regLineChange(cm, changedLines[i], "text");
   });
 }
 // Finds the line to start with when starting a parse. Tries to
 // find a line with a stateAfter, so that it can start with a
 // valid state. If that fails, it returns the line with the
 // smallest indentation, which tends to need the least context to
 // parse correctly.
 function findStartLine(cm, n, precise) {
   var minindent, minline, doc = cm.doc;
   var lim = precise ? -1 : n - (cm.doc.mode.innerMode ? 1000 : 100);
   for (var search = n; search > lim; --search) {
     if (search <= doc.first) return doc.first;
     var line = getLine(doc, search - 1);
     if (line.stateAfter && (!precise || search <= doc.frontier)) return search;
     var indented = countColumn(line.text, null, cm.options.tabSize);
     if (minline == null || minindent > indented) {
       minline = search - 1;
       minindent = indented;
     }
   }
   return minline;
 }
 function getStateBefore(cm, n, precise) {
   var doc = cm.doc, display = cm.display;
   if (!doc.mode.startState) return true;
   var pos = findStartLine(cm, n, precise), state = pos > doc.first && getLine(doc, pos-1).stateAfter;
   if (!state) state = startState(doc.mode);
   else state = copyState(doc.mode, state);
   doc.iter(pos, n, function(line) {
     processLine(cm, line.text, state);
     var save = pos == n - 1 || pos % 5 == 0 || pos >= display.viewFrom && pos < display.viewTo;
     line.stateAfter = save ? copyState(doc.mode, state) : null;
     ++pos;
   });
   if (precise) doc.frontier = pos;
   return state;
 }
 // POSITION MEASUREMENT
 function paddingTop(display) {return display.lineSpace.offsetTop;}
 function paddingVert(display) {return display.mover.offsetHeight - display.lineSpace.offsetHeight;}
 function paddingH(display) {
   if (display.cachedPaddingH) return display.cachedPaddingH;
   var e = removeChildrenAndAdd(display.measure, elt("pre", "x"));
   var style = window.getComputedStyle ? window.getComputedStyle(e) : e.currentStyle;
   var data = {left: parseInt(style.paddingLeft), right: parseInt(style.paddingRight)};
   if (!isNaN(data.left) && !isNaN(data.right)) display.cachedPaddingH = data;
   return data;
 }
 function scrollGap(cm) { return scrollerGap - cm.display.nativeBarWidth; }
 function displayWidth(cm) {
   return cm.display.scroller.clientWidth - scrollGap(cm) - cm.display.barWidth;
 }
 function displayHeight(cm) {
   return cm.display.scroller.clientHeight - scrollGap(cm) - cm.display.barHeight;
 }
 // Ensure the lineView.wrapping.heights array is populated. This is
 // an array of bottom offsets for the lines that make up a drawn
 // line. When lineWrapping is on, there might be more than one
 // height.
 function ensureLineHeights(cm, lineView, rect) {
   var wrapping = cm.options.lineWrapping;
   var curWidth = wrapping && displayWidth(cm);
   if (!lineView.measure.heights || wrapping && lineView.measure.width != curWidth) {
     var heights = lineView.measure.heights = [];
     if (wrapping) {
       lineView.measure.width = curWidth;
       var rects = lineView.text.firstChild.getClientRects();
       for (var i = 0; i < rects.length - 1; i++) {
         var cur = rects[i], next = rects[i + 1];
         if (Math.abs(cur.bottom - next.bottom) > 2)
           heights.push((cur.bottom + next.top) / 2 - rect.top);
       }
     }
     heights.push(rect.bottom - rect.top);
   }
 }
 // Find a line map (mapping character offsets to text nodes) and a
 // measurement cache for the given line number. (A line view might
 // contain multiple lines when collapsed ranges are present.)
 function mapFromLineView(lineView, line, lineN) {
   if (lineView.line == line)
     return {map: lineView.measure.map, cache: lineView.measure.cache};
   for (var i = 0; i < lineView.rest.length; i++)
     if (lineView.rest[i] == line)
       return {map: lineView.measure.maps[i], cache: lineView.measure.caches[i]};
   for (var i = 0; i < lineView.rest.length; i++)
     if (lineNo(lineView.rest[i]) > lineN)
       return {map: lineView.measure.maps[i], cache: lineView.measure.caches[i], before: true};
 }
 // Render a line into the hidden node display.externalMeasured. Used
 // when measurement is needed for a line that's not in the viewport.
 function updateExternalMeasurement(cm, line) {
   line = visualLine(line);
   var lineN = lineNo(line);
   var view = cm.display.externalMeasured = new LineView(cm.doc, line, lineN);
   view.lineN = lineN;
   var built = view.built = buildLineContent(cm, view);
   view.text = built.pre;
   removeChildrenAndAdd(cm.display.lineMeasure, built.pre);
   return view;
 }
 // Get a {top, bottom, left, right} box (in line-local coordinates)
 // for a given character.
 function measureChar(cm, line, ch, bias) {
   return measureCharPrepared(cm, prepareMeasureForLine(cm, line), ch, bias);
 }
 // Find a line view that corresponds to the given line number.
 function findViewForLine(cm, lineN) {
   if (lineN >= cm.display.viewFrom && lineN < cm.display.viewTo)
     return cm.display.view[findViewIndex(cm, lineN)];
   var ext = cm.display.externalMeasured;
   if (ext && lineN >= ext.lineN && lineN < ext.lineN + ext.size)
     return ext;
 }
 // Measurement can be split in two steps, the set-up work that
 // applies to the whole line, and the measurement of the actual
 // character. Functions like coordsChar, that need to do a lot of
 // measurements in a row, can thus ensure that the set-up work is
 // only done once.
 function prepareMeasureForLine(cm, line) {
   var lineN = lineNo(line);
   var view = findViewForLine(cm, lineN);
   if (view && !view.text) {
     view = null;
   } else if (view && view.changes) {
     updateLineForChanges(cm, view, lineN, getDimensions(cm));
     cm.curOp.forceUpdate = true;
   }
   if (!view)
     view = updateExternalMeasurement(cm, line);
   var info = mapFromLineView(view, line, lineN);
   return {
     line: line, view: view, rect: null,
     map: info.map, cache: info.cache, before: info.before,
     hasHeights: false
   };
 }
 // Given a prepared measurement object, measures the position of an
 // actual character (or fetches it from the cache).
 function measureCharPrepared(cm, prepared, ch, bias, varHeight) {
   if (prepared.before) ch = -1;
   var key = ch + (bias || ""), found;
   if (prepared.cache.hasOwnProperty(key)) {
     found = prepared.cache[key];
   } else {
     if (!prepared.rect)
       prepared.rect = prepared.view.text.getBoundingClientRect();
     if (!prepared.hasHeights) {
       ensureLineHeights(cm, prepared.view, prepared.rect);
       prepared.hasHeights = true;
     }
     found = measureCharInner(cm, prepared, ch, bias);
     if (!found.bogus) prepared.cache[key] = found;
   }
   return {left: found.left, right: found.right,
           top: varHeight ? found.rtop : found.top,
           bottom: varHeight ? found.rbottom : found.bottom};
 }
 var nullRect = {left: 0, right: 0, top: 0, bottom: 0};
 function nodeAndOffsetInLineMap(map, ch, bias) {
   var node, start, end, collapse;
   // First, search the line map for the text node corresponding to,
   // or closest to, the target character.
   for (var i = 0; i < map.length; i += 3) {
     var mStart = map[i], mEnd = map[i + 1];
     if (ch < mStart) {
       start = 0; end = 1;
       collapse = "left";
     } else if (ch < mEnd) {
       start = ch - mStart;
       end = start + 1;
     } else if (i == map.length - 3 || ch == mEnd && map[i + 3] > ch) {
       end = mEnd - mStart;
       start = end - 1;
       if (ch >= mEnd) collapse = "right";
     }
     if (start != null) {
       node = map[i + 2];
       if (mStart == mEnd && bias == (node.insertLeft ? "left" : "right"))
         collapse = bias;
       if (bias == "left" && start == 0)
         while (i && map[i - 2] == map[i - 3] && map[i - 1].insertLeft) {
           node = map[(i -= 3) + 2];
           collapse = "left";
         }
       if (bias == "right" && start == mEnd - mStart)
         while (i < map.length - 3 && map[i + 3] == map[i + 4] && !map[i + 5].insertLeft) {
           node = map[(i += 3) + 2];
           collapse = "right";
         }
       break;
     }
   }
   return {node: node, start: start, end: end, collapse: collapse, coverStart: mStart, coverEnd: mEnd};
 }
 function measureCharInner(cm, prepared, ch, bias) {
   var place = nodeAndOffsetInLineMap(prepared.map, ch, bias);
   var node = place.node, start = place.start, end = place.end, collapse = place.collapse;
   var rect;
   if (node.nodeType == 3) { // If it is a text node, use a range to retrieve the coordinates.
     for (var i = 0; i < 4; i++) { // Retry a maximum of 4 times when nonsense rectangles are returned
       while (start && isExtendingChar(prepared.line.text.charAt(place.coverStart + start))) --start;
       while (place.coverStart + end < place.coverEnd && isExtendingChar(prepared.line.text.charAt(place.coverStart + end))) ++end;
       if (ie && ie_version < 9 && start == 0 && end == place.coverEnd - place.coverStart) {
         rect = node.parentNode.getBoundingClientRect();
       } else if (ie && cm.options.lineWrapping) {
         var rects = range(node, start, end).getClientRects();
         if (rects.length)
           rect = rects[bias == "right" ? rects.length - 1 : 0];
         else
           rect = nullRect;
       } else {
         rect = range(node, start, end).getBoundingClientRect() || nullRect;
       }
       if (rect.left || rect.right || start == 0) break;
       end = start;
       start = start - 1;
       collapse = "right";
     }
     if (ie && ie_version < 11) rect = maybeUpdateRectForZooming(cm.display.measure, rect);
   } else { // If it is a widget, simply get the box for the whole widget.
     if (start > 0) collapse = bias = "right";
     var rects;
     if (cm.options.lineWrapping && (rects = node.getClientRects()).length > 1)
       rect = rects[bias == "right" ? rects.length - 1 : 0];
     else
       rect = node.getBoundingClientRect();
   }
   if (ie && ie_version < 9 && !start && (!rect || !rect.left && !rect.right)) {
     var rSpan = node.parentNode.getClientRects()[0];
     if (rSpan)
       rect = {left: rSpan.left, right: rSpan.left + charWidth(cm.display), top: rSpan.top, bottom: rSpan.bottom};
     else
       rect = nullRect;
   }
   var rtop = rect.top - prepared.rect.top, rbot = rect.bottom - prepared.rect.top;
   var mid = (rtop + rbot) / 2;
   var heights = prepared.view.measure.heights;
   for (var i = 0; i < heights.length - 1; i++)
     if (mid < heights[i]) break;
   var top = i ? heights[i - 1] : 0, bot = heights[i];
   var result = {left: (collapse == "right" ? rect.right : rect.left) - prepared.rect.left,
                 right: (collapse == "left" ? rect.left : rect.right) - prepared.rect.left,
                 top: top, bottom: bot};
   if (!rect.left && !rect.right) result.bogus = true;
   if (!cm.options.singleCursorHeightPerLine) { result.rtop = rtop; result.rbottom = rbot; }
   return result;
 }
 // Work around problem with bounding client rects on ranges being
 // returned incorrectly when zoomed on IE10 and below.
 function maybeUpdateRectForZooming(measure, rect) {
   if (!window.screen || screen.logicalXDPI == null ||
       screen.logicalXDPI == screen.deviceXDPI || !hasBadZoomedRects(measure))
     return rect;
   var scaleX = screen.logicalXDPI / screen.deviceXDPI;
   var scaleY = screen.logicalYDPI / screen.deviceYDPI;
   return {left: rect.left * scaleX, right: rect.right * scaleX,
           top: rect.top * scaleY, bottom: rect.bottom * scaleY};
 }
 function clearLineMeasurementCacheFor(lineView) {
   if (lineView.measure) {
     lineView.measure.cache = {};
     lineView.measure.heights = null;
     if (lineView.rest) for (var i = 0; i < lineView.rest.length; i++)
       lineView.measure.caches[i] = {};
   }
 }
 function clearLineMeasurementCache(cm) {
   cm.display.externalMeasure = null;
   removeChildren(cm.display.lineMeasure);
   for (var i = 0; i < cm.display.view.length; i++)
     clearLineMeasurementCacheFor(cm.display.view[i]);
 }
 function clearCaches(cm) {
   clearLineMeasurementCache(cm);
   cm.display.cachedCharWidth = cm.display.cachedTextHeight = cm.display.cachedPaddingH = null;
   if (!cm.options.lineWrapping) cm.display.maxLineChanged = true;
   cm.display.lineNumChars = null;
 }
 function pageScrollX() { return window.pageXOffset || (document.documentElement || document.body).scrollLeft; }
 function pageScrollY() { return window.pageYOffset || (document.documentElement || document.body).scrollTop; }
 // Converts a {top, bottom, left, right} box from line-local
 // coordinates into another coordinate system. Context may be one of
 // "line", "div" (display.lineDiv), "local"/null (editor), "window",
 // or "page".
 function intoCoordSystem(cm, lineObj, rect, context) {
   if (lineObj.widgets) for (var i = 0; i < lineObj.widgets.length; ++i) if (lineObj.widgets[i].above) {
     var size = widgetHeight(lineObj.widgets[i]);
     rect.top += size; rect.bottom += size;
   }
   if (context == "line") return rect;
   if (!context) context = "local";
   var yOff = heightAtLine(lineObj);
   if (context == "local") yOff += paddingTop(cm.display);
   else yOff -= cm.display.viewOffset;
   if (context == "page" || context == "window") {
     var lOff = cm.display.lineSpace.getBoundingClientRect();
     yOff += lOff.top + (context == "window" ? 0 : pageScrollY());
     var xOff = lOff.left + (context == "window" ? 0 : pageScrollX());
     rect.left += xOff; rect.right += xOff;
   }
   rect.top += yOff; rect.bottom += yOff;
   return rect;
 }
 // Coverts a box from "div" coords to another coordinate system.
 // Context may be "window", "page", "div", or "local"/null.
 function fromCoordSystem(cm, coords, context) {
   if (context == "div") return coords;
   var left = coords.left, top = coords.top;
   // First move into "page" coordinate system
   if (context == "page") {
     left -= pageScrollX();
     top -= pageScrollY();
   } else if (context == "local" || !context) {
     var localBox = cm.display.sizer.getBoundingClientRect();
     left += localBox.left;
     top += localBox.top;
   }
   var lineSpaceBox = cm.display.lineSpace.getBoundingClientRect();
   return {left: left - lineSpaceBox.left, top: top - lineSpaceBox.top};
 }
 function charCoords(cm, pos, context, lineObj, bias) {
   if (!lineObj) lineObj = getLine(cm.doc, pos.line);
   return intoCoordSystem(cm, lineObj, measureChar(cm, lineObj, pos.ch, bias), context);
 }
 // Returns a box for a given cursor position, which may have an
 // 'other' property containing the position of the secondary cursor
 // on a bidi boundary.
 function cursorCoords(cm, pos, context, lineObj, preparedMeasure, varHeight) {
   lineObj = lineObj || getLine(cm.doc, pos.line);
   if (!preparedMeasure) preparedMeasure = prepareMeasureForLine(cm, lineObj);
   function get(ch, right) {
     var m = measureCharPrepared(cm, preparedMeasure, ch, right ? "right" : "left", varHeight);
     if (right) m.left = m.right; else m.right = m.left;
     return intoCoordSystem(cm, lineObj, m, context);
   }
   function getBidi(ch, partPos) {
     var part = order[partPos], right = part.level % 2;
     if (ch == bidiLeft(part) && partPos && part.level < order[partPos - 1].level) {
       part = order[--partPos];
       ch = bidiRight(part) - (part.level % 2 ? 0 : 1);
       right = true;
     } else if (ch == bidiRight(part) && partPos < order.length - 1 && part.level < order[partPos + 1].level) {
       part = order[++partPos];
       ch = bidiLeft(part) - part.level % 2;
       right = false;
     }
     if (right && ch == part.to && ch > part.from) return get(ch - 1);
     return get(ch, right);
   }
   var order = getOrder(lineObj), ch = pos.ch;
   if (!order) return get(ch);
   var partPos = getBidiPartAt(order, ch);
   var val = getBidi(ch, partPos);
   if (bidiOther != null) val.other = getBidi(ch, bidiOther);
   return val;
 }
 // Used to cheaply estimate the coordinates for a position. Used for
 // intermediate scroll updates.
 function estimateCoords(cm, pos) {
   var left = 0, pos = clipPos(cm.doc, pos);
   if (!cm.options.lineWrapping) left = charWidth(cm.display) * pos.ch;
   var lineObj = getLine(cm.doc, pos.line);
   var top = heightAtLine(lineObj) + paddingTop(cm.display);
   return {left: left, right: left, top: top, bottom: top + lineObj.height};
 }
 // Positions returned by coordsChar contain some extra information.
 // xRel is the relative x position of the input coordinates compared
 // to the found position (so xRel > 0 means the coordinates are to
 // the right of the character position, for example). When outside
 // is true, that means the coordinates lie outside the line's
 // vertical range.
 function PosWithInfo(line, ch, outside, xRel) {
   var pos = Pos(line, ch);
   pos.xRel = xRel;
   if (outside) pos.outside = true;
   return pos;
 }
 // Compute the character position closest to the given coordinates.
 // Input must be lineSpace-local ("div" coordinate system).
 function coordsChar(cm, x, y) {
   var doc = cm.doc;
   y += cm.display.viewOffset;
   if (y < 0) return PosWithInfo(doc.first, 0, true, -1);
   var lineN = lineAtHeight(doc, y), last = doc.first + doc.size - 1;
   if (lineN > last)
     return PosWithInfo(doc.first + doc.size - 1, getLine(doc, last).text.length, true, 1);
   if (x < 0) x = 0;
   var lineObj = getLine(doc, lineN);
   for (;;) {
     var found = coordsCharInner(cm, lineObj, lineN, x, y);
     var merged = collapsedSpanAtEnd(lineObj);
     var mergedPos = merged && merged.find(0, true);
     if (merged && (found.ch > mergedPos.from.ch || found.ch == mergedPos.from.ch && found.xRel > 0))
       lineN = lineNo(lineObj = mergedPos.to.line);
     else
       return found;
   }
 }
 function coordsCharInner(cm, lineObj, lineNo, x, y) {
   var innerOff = y - heightAtLine(lineObj);
   var wrongLine = false, adjust = 2 * cm.display.wrapper.clientWidth;
   var preparedMeasure = prepareMeasureForLine(cm, lineObj);
   function getX(ch) {
     var sp = cursorCoords(cm, Pos(lineNo, ch), "line", lineObj, preparedMeasure);
     wrongLine = true;
     if (innerOff > sp.bottom) return sp.left - adjust;
     else if (innerOff < sp.top) return sp.left + adjust;
     else wrongLine = false;
     return sp.left;
   }
   var bidi = getOrder(lineObj), dist = lineObj.text.length;
   var from = lineLeft(lineObj), to = lineRight(lineObj);
   var fromX = getX(from), fromOutside = wrongLine, toX = getX(to), toOutside = wrongLine;
   if (x > toX) return PosWithInfo(lineNo, to, toOutside, 1);
   // Do a binary search between these bounds.
   for (;;) {
     if (bidi ? to == from || to == moveVisually(lineObj, from, 1) : to - from <= 1) {
       var ch = x < fromX || x - fromX <= toX - x ? from : to;
       var xDiff = x - (ch == from ? fromX : toX);
       while (isExtendingChar(lineObj.text.charAt(ch))) ++ch;
       var pos = PosWithInfo(lineNo, ch, ch == from ? fromOutside : toOutside,
                             xDiff < -1 ? -1 : xDiff > 1 ? 1 : 0);
       return pos;
     }
     var step = Math.ceil(dist / 2), middle = from + step;
     if (bidi) {
       middle = from;
       for (var i = 0; i < step; ++i) middle = moveVisually(lineObj, middle, 1);
     }
     var middleX = getX(middle);
     if (middleX > x) {to = middle; toX = middleX; if (toOutside = wrongLine) toX += 1000; dist = step;}
     else {from = middle; fromX = middleX; fromOutside = wrongLine; dist -= step;}
   }
 }
 var measureText;
 // Compute the default text height.
 function textHeight(display) {
   if (display.cachedTextHeight != null) return display.cachedTextHeight;
   if (measureText == null) {
     measureText = elt("pre");
     // Measure a bunch of lines, for browsers that compute
     // fractional heights.
     for (var i = 0; i < 49; ++i) {
       measureText.appendChild(document.createTextNode("x"));
       measureText.appendChild(elt("br"));
     }
     measureText.appendChild(document.createTextNode("x"));
   }
   removeChildrenAndAdd(display.measure, measureText);
   var height = measureText.offsetHeight / 50;
   if (height > 3) display.cachedTextHeight = height;
   removeChildren(display.measure);
   return height || 1;
 }
 // Compute the default character width.
 function charWidth(display) {
   if (display.cachedCharWidth != null) return display.cachedCharWidth;
   var anchor = elt("span", "xxxxxxxxxx");
   var pre = elt("pre", [anchor]);
   removeChildrenAndAdd(display.measure, pre);
   var rect = anchor.getBoundingClientRect(), width = (rect.right - rect.left) / 10;
   if (width > 2) display.cachedCharWidth = width;
   return width || 10;
 }
 // OPERATIONS
 // Operations are used to wrap a series of changes to the editor
 // state in such a way that each change won't have to update the
 // cursor and display (which would be awkward, slow, and
 // error-prone). Instead, display updates are batched and then all
 // combined and executed at once.
 var operationGroup = null;
 var nextOpId = 0;
 // Start a new operation.
 function startOperation(cm) {
   cm.curOp = {
     cm: cm,
     viewChanged: false,      // Flag that indicates that lines might need to be redrawn
     startHeight: cm.doc.height, // Used to detect need to update scrollbar
     forceUpdate: false,      // Used to force a redraw
     updateInput: null,       // Whether to reset the input textarea
     typing: false,           // Whether this reset should be careful to leave existing text (for compositing)
     changeObjs: null,        // Accumulated changes, for firing change events
     cursorActivityHandlers: null, // Set of handlers to fire cursorActivity on
     cursorActivityCalled: 0, // Tracks which cursorActivity handlers have been called already
     selectionChanged: false, // Whether the selection needs to be redrawn
     updateMaxLine: false,    // Set when the widest line needs to be determined anew
     scrollLeft: null, scrollTop: null, // Intermediate scroll position, not pushed to DOM yet
     scrollToPos: null,       // Used to scroll to a specific position
     focus: false,
     id: ++nextOpId           // Unique ID
   };
   if (operationGroup) {
     operationGroup.ops.push(cm.curOp);
   } else {
     cm.curOp.ownsGroup = operationGroup = {
       ops: [cm.curOp],
       delayedCallbacks: []
     };
   }
 }
 function fireCallbacksForOps(group) {
   // Calls delayed callbacks and cursorActivity handlers until no
   // new ones appear
   var callbacks = group.delayedCallbacks, i = 0;
   do {
     for (; i < callbacks.length; i++)
       callbacks[i].call(null);
     for (var j = 0; j < group.ops.length; j++) {
       var op = group.ops[j];
       if (op.cursorActivityHandlers)
         while (op.cursorActivityCalled < op.cursorActivityHandlers.length)
           op.cursorActivityHandlers[op.cursorActivityCalled++].call(null, op.cm);
     }
   } while (i < callbacks.length);
 }
 // Finish an operation, updating the display and signalling delayed events
 function endOperation(cm) {
   var op = cm.curOp, group = op.ownsGroup;
   if (!group) return;
   try { fireCallbacksForOps(group); }
   finally {
     operationGroup = null;
     for (var i = 0; i < group.ops.length; i++)
       group.ops[i].cm.curOp = null;
     endOperations(group);
   }
 }
 // The DOM updates done when an operation finishes are batched so
 // that the minimum number of relayouts are required.
 function endOperations(group) {
   var ops = group.ops;
   for (var i = 0; i < ops.length; i++) // Read DOM
     endOperation_R1(ops[i]);
   for (var i = 0; i < ops.length; i++) // Write DOM (maybe)
     endOperation_W1(ops[i]);
   for (var i = 0; i < ops.length; i++) // Read DOM
     endOperation_R2(ops[i]);
   for (var i = 0; i < ops.length; i++) // Write DOM (maybe)
     endOperation_W2(ops[i]);
   for (var i = 0; i < ops.length; i++) // Read DOM
     endOperation_finish(ops[i]);
 }
 function endOperation_R1(op) {
   var cm = op.cm, display = cm.display;
   maybeClipScrollbars(cm);
   if (op.updateMaxLine) findMaxLine(cm);
   op.mustUpdate = op.viewChanged || op.forceUpdate || op.scrollTop != null ||
     op.scrollToPos && (op.scrollToPos.from.line < display.viewFrom ||
                        op.scrollToPos.to.line >= display.viewTo) ||
     display.maxLineChanged && cm.options.lineWrapping;
   op.update = op.mustUpdate &&
     new DisplayUpdate(cm, op.mustUpdate && {top: op.scrollTop, ensure: op.scrollToPos}, op.forceUpdate);
 }
 function endOperation_W1(op) {
   op.updatedDisplay = op.mustUpdate && updateDisplayIfNeeded(op.cm, op.update);
 }
 function endOperation_R2(op) {
   var cm = op.cm, display = cm.display;
   if (op.updatedDisplay) updateHeightsInViewport(cm);
   op.barMeasure = measureForScrollbars(cm);
   // If the max line changed since it was last measured, measure it,
   // and ensure the document's width matches it.
   // updateDisplay_W2 will use these properties to do the actual resizing
   if (display.maxLineChanged && !cm.options.lineWrapping) {
     op.adjustWidthTo = measureChar(cm, display.maxLine, display.maxLine.text.length).left + 3;
     cm.display.sizerWidth = op.adjustWidthTo;
     op.barMeasure.scrollWidth =
       Math.max(display.scroller.clientWidth, display.sizer.offsetLeft + op.adjustWidthTo + scrollGap(cm) + cm.display.barWidth);
     op.maxScrollLeft = Math.max(0, display.sizer.offsetLeft + op.adjustWidthTo - displayWidth(cm));
   }
   if (op.updatedDisplay || op.selectionChanged)
     op.preparedSelection = display.input.prepareSelection();
 }
 function endOperation_W2(op) {
   var cm = op.cm;
   if (op.adjustWidthTo != null) {
     cm.display.sizer.style.minWidth = op.adjustWidthTo + "px";
     if (op.maxScrollLeft < cm.doc.scrollLeft)
       setScrollLeft(cm, Math.min(cm.display.scroller.scrollLeft, op.maxScrollLeft), true);
     cm.display.maxLineChanged = false;
   }
   if (op.preparedSelection)
     cm.display.input.showSelection(op.preparedSelection);
   if (op.updatedDisplay)
     setDocumentHeight(cm, op.barMeasure);
   if (op.updatedDisplay || op.startHeight != cm.doc.height)
     updateScrollbars(cm, op.barMeasure);
   if (op.selectionChanged) restartBlink(cm);
   if (cm.state.focused && op.updateInput)
     cm.display.input.reset(op.typing);
   if (op.focus && op.focus == activeElt()) ensureFocus(op.cm);
 }
 function endOperation_finish(op) {
   var cm = op.cm, display = cm.display, doc = cm.doc;
   if (op.updatedDisplay) postUpdateDisplay(cm, op.update);
   // Abort mouse wheel delta measurement, when scrolling explicitly
   if (display.wheelStartX != null && (op.scrollTop != null || op.scrollLeft != null || op.scrollToPos))
     display.wheelStartX = display.wheelStartY = null;
   // Propagate the scroll position to the actual DOM scroller
   if (op.scrollTop != null && (display.scroller.scrollTop != op.scrollTop || op.forceScroll)) {
     doc.scrollTop = Math.max(0, Math.min(display.scroller.scrollHeight - display.scroller.clientHeight, op.scrollTop));
     display.scrollbars.setScrollTop(doc.scrollTop);
     display.scroller.scrollTop = doc.scrollTop;
   }
   if (op.scrollLeft != null && (display.scroller.scrollLeft != op.scrollLeft || op.forceScroll)) {
     doc.scrollLeft = Math.max(0, Math.min(display.scroller.scrollWidth - displayWidth(cm), op.scrollLeft));
     display.scrollbars.setScrollLeft(doc.scrollLeft);
     display.scroller.scrollLeft = doc.scrollLeft;
     alignHorizontally(cm);
   }
   // If we need to scroll a specific position into view, do so.
   if (op.scrollToPos) {
     var coords = scrollPosIntoView(cm, clipPos(doc, op.scrollToPos.from),
                                    clipPos(doc, op.scrollToPos.to), op.scrollToPos.margin);
     if (op.scrollToPos.isCursor && cm.state.focused) maybeScrollWindow(cm, coords);
   }
   // Fire events for markers that are hidden/unidden by editing or
   // undoing
   var hidden = op.maybeHiddenMarkers, unhidden = op.maybeUnhiddenMarkers;
   if (hidden) for (var i = 0; i < hidden.length; ++i)
     if (!hidden[i].lines.length) signal(hidden[i], "hide");
   if (unhidden) for (var i = 0; i < unhidden.length; ++i)
     if (unhidden[i].lines.length) signal(unhidden[i], "unhide");
   if (display.wrapper.offsetHeight)
     doc.scrollTop = cm.display.scroller.scrollTop;
   // Fire change events, and delayed event handlers
   if (op.changeObjs)
     signal(cm, "changes", cm, op.changeObjs);
   if (op.update)
     op.update.finish();
 }
 // Run the given function in an operation
 function runInOp(cm, f) {
   if (cm.curOp) return f();
   startOperation(cm);
   try { return f(); }
   finally { endOperation(cm); }
 }
 // Wraps a function in an operation. Returns the wrapped function.
 function operation(cm, f) {
   return function() {
     if (cm.curOp) return f.apply(cm, arguments);
     startOperation(cm);
     try { return f.apply(cm, arguments); }
     finally { endOperation(cm); }
   };
 }
 // Used to add methods to editor and doc instances, wrapping them in
 // operations.
 function methodOp(f) {
   return function() {
     if (this.curOp) return f.apply(this, arguments);
     startOperation(this);
     try { return f.apply(this, arguments); }
     finally { endOperation(this); }
   };
 }
 function docMethodOp(f) {
   return function() {
     var cm = this.cm;
     if (!cm || cm.curOp) return f.apply(this, arguments);
     startOperation(cm);
     try { return f.apply(this, arguments); }
     finally { endOperation(cm); }
   };
 }
 // VIEW TRACKING
 // These objects are used to represent the visible (currently drawn)
 // part of the document. A LineView may correspond to multiple
 // logical lines, if those are connected by collapsed ranges.
 function LineView(doc, line, lineN) {
   // The starting line
   this.line = line;
   // Continuing lines, if any
   this.rest = visualLineContinued(line);
   // Number of logical lines in this visual line
   this.size = this.rest ? lineNo(lst(this.rest)) - lineN + 1 : 1;
   this.node = this.text = null;
   this.hidden = lineIsHidden(doc, line);
 }
 // Create a range of LineView objects for the given lines.
 function buildViewArray(cm, from, to) {
   var array = [], nextPos;
   for (var pos = from; pos < to; pos = nextPos) {
     var view = new LineView(cm.doc, getLine(cm.doc, pos), pos);
     nextPos = pos + view.size;
     array.push(view);
   }
   return array;
 }
 // Updates the display.view data structure for a given change to the
 // document. From and to are in pre-change coordinates. Lendiff is
 // the amount of lines added or subtracted by the change. This is
 // used for changes that span multiple lines, or change the way
 // lines are divided into visual lines. regLineChange (below)
 // registers single-line changes.
 function regChange(cm, from, to, lendiff) {
   if (from == null) from = cm.doc.first;
   if (to == null) to = cm.doc.first + cm.doc.size;
   if (!lendiff) lendiff = 0;
   var display = cm.display;
   if (lendiff && to < display.viewTo &&
       (display.updateLineNumbers == null || display.updateLineNumbers > from))
     display.updateLineNumbers = from;
   cm.curOp.viewChanged = true;
   if (from >= display.viewTo) { // Change after
     if (sawCollapsedSpans && visualLineNo(cm.doc, from) < display.viewTo)
       resetView(cm);
   } else if (to <= display.viewFrom) { // Change before
     if (sawCollapsedSpans && visualLineEndNo(cm.doc, to + lendiff) > display.viewFrom) {
       resetView(cm);
     } else {
       display.viewFrom += lendiff;
       display.viewTo += lendiff;
     }
   } else if (from <= display.viewFrom && to >= display.viewTo) { // Full overlap
     resetView(cm);
   } else if (from <= display.viewFrom) { // Top overlap
     var cut = viewCuttingPoint(cm, to, to + lendiff, 1);
     if (cut) {
       display.view = display.view.slice(cut.index);
       display.viewFrom = cut.lineN;
       display.viewTo += lendiff;
     } else {
       resetView(cm);
     }
   } else if (to >= display.viewTo) { // Bottom overlap
     var cut = viewCuttingPoint(cm, from, from, -1);
     if (cut) {
       display.view = display.view.slice(0, cut.index);
       display.viewTo = cut.lineN;
     } else {
       resetView(cm);
     }
   } else { // Gap in the middle
     var cutTop = viewCuttingPoint(cm, from, from, -1);
     var cutBot = viewCuttingPoint(cm, to, to + lendiff, 1);
     if (cutTop && cutBot) {
       display.view = display.view.slice(0, cutTop.index)
         .concat(buildViewArray(cm, cutTop.lineN, cutBot.lineN))
         .concat(display.view.slice(cutBot.index));
       display.viewTo += lendiff;
     } else {
       resetView(cm);
     }
   }
   var ext = display.externalMeasured;
   if (ext) {
     if (to < ext.lineN)
       ext.lineN += lendiff;
     else if (from < ext.lineN + ext.size)
       display.externalMeasured = null;
   }
 }
 // Register a change to a single line. Type must be one of "text",
 // "gutter", "class", "widget"
 function regLineChange(cm, line, type) {
   cm.curOp.viewChanged = true;
   var display = cm.display, ext = cm.display.externalMeasured;
   if (ext && line >= ext.lineN && line < ext.lineN + ext.size)
     display.externalMeasured = null;
   if (line < display.viewFrom || line >= display.viewTo) return;
   var lineView = display.view[findViewIndex(cm, line)];
   if (lineView.node == null) return;
   var arr = lineView.changes || (lineView.changes = []);
   if (indexOf(arr, type) == -1) arr.push(type);
 }
 // Clear the view.
 function resetView(cm) {
   cm.display.viewFrom = cm.display.viewTo = cm.doc.first;
   cm.display.view = [];
   cm.display.viewOffset = 0;
 }
 // Find the view element corresponding to a given line. Return null
 // when the line isn't visible.
 function findViewIndex(cm, n) {
   if (n >= cm.display.viewTo) return null;
   n -= cm.display.viewFrom;
   if (n < 0) return null;
   var view = cm.display.view;
   for (var i = 0; i < view.length; i++) {
     n -= view[i].size;
     if (n < 0) return i;
   }
 }
 function viewCuttingPoint(cm, oldN, newN, dir) {
   var index = findViewIndex(cm, oldN), diff, view = cm.display.view;
   if (!sawCollapsedSpans || newN == cm.doc.first + cm.doc.size)
     return {index: index, lineN: newN};
   for (var i = 0, n = cm.display.viewFrom; i < index; i++)
     n += view[i].size;
   if (n != oldN) {
     if (dir > 0) {
       if (index == view.length - 1) return null;
       diff = (n + view[index].size) - oldN;
       index++;
     } else {
       diff = n - oldN;
     }
     oldN += diff; newN += diff;
   }
   while (visualLineNo(cm.doc, newN) != newN) {
     if (index == (dir < 0 ? 0 : view.length - 1)) return null;
     newN += dir * view[index - (dir < 0 ? 1 : 0)].size;
     index += dir;
   }
   return {index: index, lineN: newN};
 }
 // Force the view to cover a given range, adding empty view element
 // or clipping off existing ones as needed.
 function adjustView(cm, from, to) {
   var display = cm.display, view = display.view;
   if (view.length == 0 || from >= display.viewTo || to <= display.viewFrom) {
     display.view = buildViewArray(cm, from, to);
     display.viewFrom = from;
   } else {
     if (display.viewFrom > from)
       display.view = buildViewArray(cm, from, display.viewFrom).concat(display.view);
     else if (display.viewFrom < from)
       display.view = display.view.slice(findViewIndex(cm, from));
     display.viewFrom = from;
     if (display.viewTo < to)
       display.view = display.view.concat(buildViewArray(cm, display.viewTo, to));
     else if (display.viewTo > to)
       display.view = display.view.slice(0, findViewIndex(cm, to));
   }
   display.viewTo = to;
 }
 // Count the number of lines in the view whose DOM representation is
 // out of date (or nonexistent).
 function countDirtyView(cm) {
   var view = cm.display.view, dirty = 0;
   for (var i = 0; i < view.length; i++) {
     var lineView = view[i];
     if (!lineView.hidden && (!lineView.node || lineView.changes)) ++dirty;
   }
   return dirty;
 }
 // EVENT HANDLERS
 // Attach the necessary event handlers when initializing the editor
 function registerEventHandlers(cm) {
   var d = cm.display;
   on(d.scroller, "mousedown", operation(cm, onMouseDown));
   // Older IE's will not fire a second mousedown for a double click
   if (ie && ie_version < 11)
     on(d.scroller, "dblclick", operation(cm, function(e) {
       if (signalDOMEvent(cm, e)) return;
       var pos = posFromMouse(cm, e);
       if (!pos || clickInGutter(cm, e) || eventInWidget(cm.display, e)) return;
       e_preventDefault(e);
       var word = cm.findWordAt(pos);
       extendSelection(cm.doc, word.anchor, word.head);
     }));
   else
     on(d.scroller, "dblclick", function(e) { signalDOMEvent(cm, e) || e_preventDefault(e); });
   // Some browsers fire contextmenu *after* opening the menu, at
   // which point we can't mess with it anymore. Context menu is
   // handled in onMouseDown for these browsers.
   if (!captureRightClick) on(d.scroller, "contextmenu", function(e) {onContextMenu(cm, e);});
   // Used to suppress mouse event handling when a touch happens
   var touchFinished, prevTouch = {end: 0};
   function finishTouch() {
     if (d.activeTouch) {
       touchFinished = setTimeout(function() {d.activeTouch = null;}, 1000);
       prevTouch = d.activeTouch;
       prevTouch.end = +new Date;
     }
   };
   function isMouseLikeTouchEvent(e) {
     if (e.touches.length != 1) return false;
     var touch = e.touches[0];
     return touch.radiusX <= 1 && touch.radiusY <= 1;
   }
   function farAway(touch, other) {
     if (other.left == null) return true;
     var dx = other.left - touch.left, dy = other.top - touch.top;
     return dx * dx + dy * dy > 20 * 20;
   }
   on(d.scroller, "touchstart", function(e) {
     if (!isMouseLikeTouchEvent(e)) {
       clearTimeout(touchFinished);
       var now = +new Date;
       d.activeTouch = {start: now, moved: false,
                        prev: now - prevTouch.end <= 300 ? prevTouch : null};
       if (e.touches.length == 1) {
         d.activeTouch.left = e.touches[0].pageX;
         d.activeTouch.top = e.touches[0].pageY;
       }
     }
   });
   on(d.scroller, "touchmove", function() {
     if (d.activeTouch) d.activeTouch.moved = true;
   });
   on(d.scroller, "touchend", function(e) {
     var touch = d.activeTouch;
     if (touch && !eventInWidget(d, e) && touch.left != null &&
         !touch.moved && new Date - touch.start < 300) {
       var pos = cm.coordsChar(d.activeTouch, "page"), range;
       if (!touch.prev || farAway(touch, touch.prev)) // Single tap
         range = new Range(pos, pos);
       else if (!touch.prev.prev || farAway(touch, touch.prev.prev)) // Double tap
         range = cm.findWordAt(pos);
       else // Triple tap
         range = new Range(Pos(pos.line, 0), clipPos(cm.doc, Pos(pos.line + 1, 0)));
       cm.setSelection(range.anchor, range.head);
       cm.focus();
       e_preventDefault(e);
     }
     finishTouch();
   });
   on(d.scroller, "touchcancel", finishTouch);
   // Sync scrolling between fake scrollbars and real scrollable
   // area, ensure viewport is updated when scrolling.
   on(d.scroller, "scroll", function() {
     if (d.scroller.clientHeight) {
       setScrollTop(cm, d.scroller.scrollTop);
       setScrollLeft(cm, d.scroller.scrollLeft, true);
       signal(cm, "scroll", cm);
     }
   });
   // Listen to wheel events in order to try and update the viewport on time.
   on(d.scroller, "mousewheel", function(e){onScrollWheel(cm, e);});
   on(d.scroller, "DOMMouseScroll", function(e){onScrollWheel(cm, e);});
   // Prevent wrapper from ever scrolling
   on(d.wrapper, "scroll", function() { d.wrapper.scrollTop = d.wrapper.scrollLeft = 0; });
   d.dragFunctions = {
     enter: function(e) {if (!signalDOMEvent(cm, e)) e_stop(e);},
     over: function(e) {if (!signalDOMEvent(cm, e)) { onDragOver(cm, e); e_stop(e); }},
     start: function(e){onDragStart(cm, e);},
     drop: operation(cm, onDrop),
     leave: function() {clearDragCursor(cm);}
   };
   var inp = d.input.getField();
   on(inp, "keyup", function(e) { onKeyUp.call(cm, e); });
   on(inp, "keydown", operation(cm, onKeyDown));
   on(inp, "keypress", operation(cm, onKeyPress));
   on(inp, "focus", bind(onFocus, cm));
   on(inp, "blur", bind(onBlur, cm));
 }
 function dragDropChanged(cm, value, old) {
   var wasOn = old && old != CodeMirror.Init;
   if (!value != !wasOn) {
     var funcs = cm.display.dragFunctions;
     var toggle = value ? on : off;
     toggle(cm.display.scroller, "dragstart", funcs.start);
     toggle(cm.display.scroller, "dragenter", funcs.enter);
     toggle(cm.display.scroller, "dragover", funcs.over);
     toggle(cm.display.scroller, "dragleave", funcs.leave);
     toggle(cm.display.scroller, "drop", funcs.drop);
   }
 }
 // Called when the window resizes
 function onResize(cm) {
   var d = cm.display;
   if (d.lastWrapHeight == d.wrapper.clientHeight && d.lastWrapWidth == d.wrapper.clientWidth)
     return;
   // Might be a text scaling operation, clear size caches.
   d.cachedCharWidth = d.cachedTextHeight = d.cachedPaddingH = null;
   d.scrollbarsClipped = false;
   cm.setSize();
 }
 // MOUSE EVENTS
 // Return true when the given mouse event happened in a widget
 function eventInWidget(display, e) {
   for (var n = e_target(e); n != display.wrapper; n = n.parentNode) {
     if (!n || (n.nodeType == 1 && n.getAttribute("cm-ignore-events") == "true") ||
         (n.parentNode == display.sizer && n != display.mover))
       return true;
   }
 }
 // Given a mouse event, find the corresponding position. If liberal
 // is false, it checks whether a gutter or scrollbar was clicked,
 // and returns null if it was. forRect is used by rectangular
 // selections, and tries to estimate a character position even for
 // coordinates beyond the right of the text.
 function posFromMouse(cm, e, liberal, forRect) {
   var display = cm.display;
   if (!liberal && e_target(e).getAttribute("cm-not-content") == "true") return null;
   var x, y, space = display.lineSpace.getBoundingClientRect();
   // Fails unpredictably on IE[67] when mouse is dragged around quickly.
   try { x = e.clientX - space.left; y = e.clientY - space.top; }
   catch (e) { return null; }
   var coords = coordsChar(cm, x, y), line;
   if (forRect && coords.xRel == 1 && (line = getLine(cm.doc, coords.line).text).length == coords.ch) {
     var colDiff = countColumn(line, line.length, cm.options.tabSize) - line.length;
     coords = Pos(coords.line, Math.max(0, Math.round((x - paddingH(cm.display).left) / charWidth(cm.display)) - colDiff));
   }
   return coords;
 }
 // A mouse down can be a single click, double click, triple click,
 // start of selection drag, start of text drag, new cursor
 // (ctrl-click), rectangle drag (alt-drag), or xwin
 // middle-click-paste. Or it might be a click on something we should
 // not interfere with, such as a scrollbar or widget.
 function onMouseDown(e) {
   var cm = this, display = cm.display;
   if (display.activeTouch && display.input.supportsTouch() || signalDOMEvent(cm, e)) return;
   display.shift = e.shiftKey;
   if (eventInWidget(display, e)) {
     if (!webkit) {
       // Briefly turn off draggability, to allow widgets to do
       // normal dragging things.
       display.scroller.draggable = false;
       setTimeout(function(){display.scroller.draggable = true;}, 100);
     }
     return;
   }
   if (clickInGutter(cm, e)) return;
   var start = posFromMouse(cm, e);
   window.focus();
   switch (e_button(e)) {
   case 1:
     // #3261: make sure, that we're not starting a second selection
     if (cm.state.selectingText)
       cm.state.selectingText(e);
     else if (start)
       leftButtonDown(cm, e, start);
     else if (e_target(e) == display.scroller)
       e_preventDefault(e);
     break;
   case 2:
     if (webkit) cm.state.lastMiddleDown = +new Date;
     if (start) extendSelection(cm.doc, start);
     setTimeout(function() {display.input.focus();}, 20);
     e_preventDefault(e);
     break;
   case 3:
     if (captureRightClick) onContextMenu(cm, e);
     else delayBlurEvent(cm);
     break;
   }
 }
 var lastClick, lastDoubleClick;
 function leftButtonDown(cm, e, start) {
   if (ie) setTimeout(bind(ensureFocus, cm), 0);
   else cm.curOp.focus = activeElt();
   var now = +new Date, type;
   if (lastDoubleClick && lastDoubleClick.time > now - 400 && cmp(lastDoubleClick.pos, start) == 0) {
     type = "triple";
   } else if (lastClick && lastClick.time > now - 400 && cmp(lastClick.pos, start) == 0) {
     type = "double";
     lastDoubleClick = {time: now, pos: start};
   } else {
     type = "single";
     lastClick = {time: now, pos: start};
   }
   var sel = cm.doc.sel, modifier = mac ? e.metaKey : e.ctrlKey, contained;
   if (cm.options.dragDrop && dragAndDrop && !isReadOnly(cm) &&
       type == "single" && (contained = sel.contains(start)) > -1 &&
       (cmp((contained = sel.ranges[contained]).from(), start) < 0 || start.xRel > 0) &&
       (cmp(contained.to(), start) > 0 || start.xRel < 0))
     leftButtonStartDrag(cm, e, start, modifier);
   else
     leftButtonSelect(cm, e, start, type, modifier);
 }
 // Start a text drag. When it ends, see if any dragging actually
 // happen, and treat as a click if it didn't.
 function leftButtonStartDrag(cm, e, start, modifier) {
   var display = cm.display, startTime = +new Date;
   var dragEnd = operation(cm, function(e2) {
     if (webkit) display.scroller.draggable = false;
     cm.state.draggingText = false;
     off(document, "mouseup", dragEnd);
     off(display.scroller, "drop", dragEnd);
     if (Math.abs(e.clientX - e2.clientX) + Math.abs(e.clientY - e2.clientY) < 10) {
       e_preventDefault(e2);
       if (!modifier && +new Date - 200 < startTime)
         extendSelection(cm.doc, start);
       // Work around unexplainable focus problem in IE9 (#2127) and Chrome (#3081)
       if (webkit || ie && ie_version == 9)
         setTimeout(function() {document.body.focus(); display.input.focus();}, 20);
       else
         display.input.focus();
     }
   });
   // Let the drag handler handle this.
   if (webkit) display.scroller.draggable = true;
   cm.state.draggingText = dragEnd;
   // IE's approach to draggable
   if (display.scroller.dragDrop) display.scroller.dragDrop();
   on(document, "mouseup", dragEnd);
   on(display.scroller, "drop", dragEnd);
 }
 // Normal selection, as opposed to text dragging.
 function leftButtonSelect(cm, e, start, type, addNew) {
   var display = cm.display, doc = cm.doc;
   e_preventDefault(e);
   var ourRange, ourIndex, startSel = doc.sel, ranges = startSel.ranges;
   if (addNew && !e.shiftKey) {
     ourIndex = doc.sel.contains(start);
     if (ourIndex > -1)
       ourRange = ranges[ourIndex];
     else
       ourRange = new Range(start, start);
   } else {
     ourRange = doc.sel.primary();
     ourIndex = doc.sel.primIndex;
   }
   if (e.altKey) {
     type = "rect";
     if (!addNew) ourRange = new Range(start, start);
     start = posFromMouse(cm, e, true, true);
     ourIndex = -1;
   } else if (type == "double") {
     var word = cm.findWordAt(start);
     if (cm.display.shift || doc.extend)
       ourRange = extendRange(doc, ourRange, word.anchor, word.head);
     else
       ourRange = word;
   } else if (type == "triple") {
     var line = new Range(Pos(start.line, 0), clipPos(doc, Pos(start.line + 1, 0)));
     if (cm.display.shift || doc.extend)
       ourRange = extendRange(doc, ourRange, line.anchor, line.head);
     else
       ourRange = line;
   } else {
     ourRange = extendRange(doc, ourRange, start);
   }
   if (!addNew) {
     ourIndex = 0;
     setSelection(doc, new Selection([ourRange], 0), sel_mouse);
     startSel = doc.sel;
   } else if (ourIndex == -1) {
     ourIndex = ranges.length;
     setSelection(doc, normalizeSelection(ranges.concat([ourRange]), ourIndex),
                  {scroll: false, origin: "*mouse"});
   } else if (ranges.length > 1 && ranges[ourIndex].empty() && type == "single" && !e.shiftKey) {
     setSelection(doc, normalizeSelection(ranges.slice(0, ourIndex).concat(ranges.slice(ourIndex + 1)), 0),
                  {scroll: false, origin: "*mouse"});
     startSel = doc.sel;
   } else {
     replaceOneSelection(doc, ourIndex, ourRange, sel_mouse);
   }
   var lastPos = start;
   function extendTo(pos) {
     if (cmp(lastPos, pos) == 0) return;
     lastPos = pos;
     if (type == "rect") {
       var ranges = [], tabSize = cm.options.tabSize;
       var startCol = countColumn(getLine(doc, start.line).text, start.ch, tabSize);
       var posCol = countColumn(getLine(doc, pos.line).text, pos.ch, tabSize);
       var left = Math.min(startCol, posCol), right = Math.max(startCol, posCol);
       for (var line = Math.min(start.line, pos.line), end = Math.min(cm.lastLine(), Math.max(start.line, pos.line));
            line <= end; line++) {
         var text = getLine(doc, line).text, leftPos = findColumn(text, left, tabSize);
         if (left == right)
           ranges.push(new Range(Pos(line, leftPos), Pos(line, leftPos)));
         else if (text.length > leftPos)
           ranges.push(new Range(Pos(line, leftPos), Pos(line, findColumn(text, right, tabSize))));
       }
       if (!ranges.length) ranges.push(new Range(start, start));
       setSelection(doc, normalizeSelection(startSel.ranges.slice(0, ourIndex).concat(ranges), ourIndex),
                    {origin: "*mouse", scroll: false});
       cm.scrollIntoView(pos);
     } else {
       var oldRange = ourRange;
       var anchor = oldRange.anchor, head = pos;
       if (type != "single") {
         if (type == "double")
           var range = cm.findWordAt(pos);
         else
           var range = new Range(Pos(pos.line, 0), clipPos(doc, Pos(pos.line + 1, 0)));
         if (cmp(range.anchor, anchor) > 0) {
           head = range.head;
           anchor = minPos(oldRange.from(), range.anchor);
         } else {
           head = range.anchor;
           anchor = maxPos(oldRange.to(), range.head);
         }
       }
       var ranges = startSel.ranges.slice(0);
       ranges[ourIndex] = new Range(clipPos(doc, anchor), head);
       setSelection(doc, normalizeSelection(ranges, ourIndex), sel_mouse);
     }
   }
   var editorSize = display.wrapper.getBoundingClientRect();
   // Used to ensure timeout re-tries don't fire when another extend
   // happened in the meantime (clearTimeout isn't reliable -- at
   // least on Chrome, the timeouts still happen even when cleared,
   // if the clear happens after their scheduled firing time).
   var counter = 0;
   function extend(e) {
     var curCount = ++counter;
     var cur = posFromMouse(cm, e, true, type == "rect");
     if (!cur) return;
     if (cmp(cur, lastPos) != 0) {
       cm.curOp.focus = activeElt();
       extendTo(cur);
       var visible = visibleLines(display, doc);
       if (cur.line >= visible.to || cur.line < visible.from)
         setTimeout(operation(cm, function(){if (counter == curCount) extend(e);}), 150);
     } else {
       var outside = e.clientY < editorSize.top ? -20 : e.clientY > editorSize.bottom ? 20 : 0;
       if (outside) setTimeout(operation(cm, function() {
         if (counter != curCount) return;
         display.scroller.scrollTop += outside;
         extend(e);
       }), 50);
     }
   }
   function done(e) {
     cm.state.selectingText = false;
     counter = Infinity;
     e_preventDefault(e);
     display.input.focus();
     off(document, "mousemove", move);
     off(document, "mouseup", up);
     doc.history.lastSelOrigin = null;
   }
   var move = operation(cm, function(e) {
     if (!e_button(e)) done(e);
     else extend(e);
   });
   var up = operation(cm, done);
   cm.state.selectingText = up;
   on(document, "mousemove", move);
   on(document, "mouseup", up);
 }
 // Determines whether an event happened in the gutter, and fires the
 // handlers for the corresponding event.
 function gutterEvent(cm, e, type, prevent, signalfn) {
   try { var mX = e.clientX, mY = e.clientY; }
   catch(e) { return false; }
   if (mX >= Math.floor(cm.display.gutters.getBoundingClientRect().right)) return false;
   if (prevent) e_preventDefault(e);
   var display = cm.display;
   var lineBox = display.lineDiv.getBoundingClientRect();
   if (mY > lineBox.bottom || !hasHandler(cm, type)) return e_defaultPrevented(e);
   mY -= lineBox.top - display.viewOffset;
   for (var i = 0; i < cm.options.gutters.length; ++i) {
     var g = display.gutters.childNodes[i];
     if (g && g.getBoundingClientRect().right >= mX) {
       var line = lineAtHeight(cm.doc, mY);
       var gutter = cm.options.gutters[i];
       signalfn(cm, type, cm, line, gutter, e);
       return e_defaultPrevented(e);
     }
   }
 }
 function clickInGutter(cm, e) {
   return gutterEvent(cm, e, "gutterClick", true, signalLater);
 }
 // Kludge to work around strange IE behavior where it'll sometimes
 // re-fire a series of drag-related events right after the drop (#1551)
 var lastDrop = 0;
 function onDrop(e) {
   var cm = this;
   clearDragCursor(cm);
   if (signalDOMEvent(cm, e) || eventInWidget(cm.display, e))
     return;
   e_preventDefault(e);
   if (ie) lastDrop = +new Date;
   var pos = posFromMouse(cm, e, true), files = e.dataTransfer.files;
   if (!pos || isReadOnly(cm)) return;
   // Might be a file drop, in which case we simply extract the text
   // and insert it.
   if (files && files.length && window.FileReader && window.File) {
     var n = files.length, text = Array(n), read = 0;
     var loadFile = function(file, i) {
       var reader = new FileReader;
       reader.onload = operation(cm, function() {
         text[i] = reader.result;
         if (++read == n) {
           pos = clipPos(cm.doc, pos);
           var change = {from: pos, to: pos,
                         text: cm.doc.splitLines(text.join(cm.doc.lineSeparator())),
                         origin: "paste"};
           makeChange(cm.doc, change);
           setSelectionReplaceHistory(cm.doc, simpleSelection(pos, changeEnd(change)));
         }
       });
       reader.readAsText(file);
     };
     for (var i = 0; i < n; ++i) loadFile(files[i], i);
   } else { // Normal drop
     // Don't do a replace if the drop happened inside of the selected text.
     if (cm.state.draggingText && cm.doc.sel.contains(pos) > -1) {
       cm.state.draggingText(e);
       // Ensure the editor is re-focused
       setTimeout(function() {cm.display.input.focus();}, 20);
       return;
     }
     try {
       var text = e.dataTransfer.getData("Text");
       if (text) {
         if (cm.state.draggingText && !(mac ? e.altKey : e.ctrlKey))
           var selected = cm.listSelections();
         setSelectionNoUndo(cm.doc, simpleSelection(pos, pos));
         if (selected) for (var i = 0; i < selected.length; ++i)
           replaceRange(cm.doc, "", selected[i].anchor, selected[i].head, "drag");
         cm.replaceSelection(text, "around", "paste");
         cm.display.input.focus();
       }
     }
     catch(e){}
   }
 }
 function onDragStart(cm, e) {
   if (ie && (!cm.state.draggingText || +new Date - lastDrop < 100)) { e_stop(e); return; }
   if (signalDOMEvent(cm, e) || eventInWidget(cm.display, e)) return;
   e.dataTransfer.setData("Text", cm.getSelection());
   // Use dummy image instead of default browsers image.
   // Recent Safari (~6.0.2) have a tendency to segfault when this happens, so we don't do it there.
   if (e.dataTransfer.setDragImage && !safari) {
     var img = elt("img", null, null, "position: fixed; left: 0; top: 0;");
     img.src = "data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==";
     if (presto) {
       img.width = img.height = 1;
       cm.display.wrapper.appendChild(img);
       // Force a relayout, or Opera won't use our image for some obscure reason
       img._top = img.offsetTop;
     }
     e.dataTransfer.setDragImage(img, 0, 0);
     if (presto) img.parentNode.removeChild(img);
   }
 }
 function onDragOver(cm, e) {
   var pos = posFromMouse(cm, e);
   if (!pos) return;
   var frag = document.createDocumentFragment();
   drawSelectionCursor(cm, pos, frag);
   if (!cm.display.dragCursor) {
     cm.display.dragCursor = elt("div", null, "CodeMirror-cursors CodeMirror-dragcursors");
     cm.display.lineSpace.insertBefore(cm.display.dragCursor, cm.display.cursorDiv);
   }
   removeChildrenAndAdd(cm.display.dragCursor, frag);
 }
 function clearDragCursor(cm) {
   if (cm.display.dragCursor) {
     cm.display.lineSpace.removeChild(cm.display.dragCursor);
     cm.display.dragCursor = null;
   }
 }
 // SCROLL EVENTS
 // Sync the scrollable area and scrollbars, ensure the viewport
 // covers the visible area.
 function setScrollTop(cm, val) {
   if (Math.abs(cm.doc.scrollTop - val) < 2) return;
   cm.doc.scrollTop = val;
   if (!gecko) updateDisplaySimple(cm, {top: val});
   if (cm.display.scroller.scrollTop != val) cm.display.scroller.scrollTop = val;
   cm.display.scrollbars.setScrollTop(val);
   if (gecko) updateDisplaySimple(cm);
   startWorker(cm, 100);
 }
 // Sync scroller and scrollbar, ensure the gutter elements are
 // aligned.
 function setScrollLeft(cm, val, isScroller) {
   if (isScroller ? val == cm.doc.scrollLeft : Math.abs(cm.doc.scrollLeft - val) < 2) return;
   val = Math.min(val, cm.display.scroller.scrollWidth - cm.display.scroller.clientWidth);
   cm.doc.scrollLeft = val;
   alignHorizontally(cm);
   if (cm.display.scroller.scrollLeft != val) cm.display.scroller.scrollLeft = val;
   cm.display.scrollbars.setScrollLeft(val);
 }
 // Since the delta values reported on mouse wheel events are
 // unstandardized between browsers and even browser versions, and
 // generally horribly unpredictable, this code starts by measuring
 // the scroll effect that the first few mouse wheel events have,
 // and, from that, detects the way it can convert deltas to pixel
 // offsets afterwards.
 //
 // The reason we want to know the amount a wheel event will scroll
 // is that it gives us a chance to update the display before the
 // actual scrolling happens, reducing flickering.
 var wheelSamples = 0, wheelPixelsPerUnit = null;
 // Fill in a browser-detected starting value on browsers where we
 // know one. These don't have to be accurate -- the result of them
 // being wrong would just be a slight flicker on the first wheel
 // scroll (if it is large enough).
 if (ie) wheelPixelsPerUnit = -.53;
 else if (gecko) wheelPixelsPerUnit = 15;
 else if (chrome) wheelPixelsPerUnit = -.7;
 else if (safari) wheelPixelsPerUnit = -1/3;
 var wheelEventDelta = function(e) {
   var dx = e.wheelDeltaX, dy = e.wheelDeltaY;
   if (dx == null && e.detail && e.axis == e.HORIZONTAL_AXIS) dx = e.detail;
   if (dy == null && e.detail && e.axis == e.VERTICAL_AXIS) dy = e.detail;
   else if (dy == null) dy = e.wheelDelta;
   return {x: dx, y: dy};
 };
 CodeMirror.wheelEventPixels = function(e) {
   var delta = wheelEventDelta(e);
   delta.x *= wheelPixelsPerUnit;
   delta.y *= wheelPixelsPerUnit;
   return delta;
 };
 function onScrollWheel(cm, e) {
   var delta = wheelEventDelta(e), dx = delta.x, dy = delta.y;
   var display = cm.display, scroll = display.scroller;
   // Quit if there's nothing to scroll here
   if (!(dx && scroll.scrollWidth > scroll.clientWidth ||
         dy && scroll.scrollHeight > scroll.clientHeight)) return;
   // Webkit browsers on OS X abort momentum scrolls when the target
   // of the scroll event is removed from the scrollable element.
   // This hack (see related code in patchDisplay) makes sure the
   // element is kept around.
   if (dy && mac && webkit) {
     outer: for (var cur = e.target, view = display.view; cur != scroll; cur = cur.parentNode) {
       for (var i = 0; i < view.length; i++) {
         if (view[i].node == cur) {
           cm.display.currentWheelTarget = cur;
           break outer;
         }
       }
     }
   }
   // On some browsers, horizontal scrolling will cause redraws to
   // happen before the gutter has been realigned, causing it to
   // wriggle around in a most unseemly way. When we have an
   // estimated pixels/delta value, we just handle horizontal
   // scrolling entirely here. It'll be slightly off from native, but
   // better than glitching out.
   if (dx && !gecko && !presto && wheelPixelsPerUnit != null) {
     if (dy)
       setScrollTop(cm, Math.max(0, Math.min(scroll.scrollTop + dy * wheelPixelsPerUnit, scroll.scrollHeight - scroll.clientHeight)));
     setScrollLeft(cm, Math.max(0, Math.min(scroll.scrollLeft + dx * wheelPixelsPerUnit, scroll.scrollWidth - scroll.clientWidth)));
     e_preventDefault(e);
     display.wheelStartX = null; // Abort measurement, if in progress
     return;
   }
   // 'Project' the visible viewport to cover the area that is being
   // scrolled into view (if we know enough to estimate it).
   if (dy && wheelPixelsPerUnit != null) {
     var pixels = dy * wheelPixelsPerUnit;
     var top = cm.doc.scrollTop, bot = top + display.wrapper.clientHeight;
     if (pixels < 0) top = Math.max(0, top + pixels - 50);
     else bot = Math.min(cm.doc.height, bot + pixels + 50);
     updateDisplaySimple(cm, {top: top, bottom: bot});
   }
   if (wheelSamples < 20) {
     if (display.wheelStartX == null) {
       display.wheelStartX = scroll.scrollLeft; display.wheelStartY = scroll.scrollTop;
       display.wheelDX = dx; display.wheelDY = dy;
       setTimeout(function() {
         if (display.wheelStartX == null) return;
         var movedX = scroll.scrollLeft - display.wheelStartX;
         var movedY = scroll.scrollTop - display.wheelStartY;
         var sample = (movedY && display.wheelDY && movedY / display.wheelDY) ||
           (movedX && display.wheelDX && movedX / display.wheelDX);
         display.wheelStartX = display.wheelStartY = null;
         if (!sample) return;
         wheelPixelsPerUnit = (wheelPixelsPerUnit * wheelSamples + sample) / (wheelSamples + 1);
         ++wheelSamples;
       }, 200);
     } else {
       display.wheelDX += dx; display.wheelDY += dy;
     }
   }
 }
 // KEY EVENTS
 // Run a handler that was bound to a key.
 function doHandleBinding(cm, bound, dropShift) {
   if (typeof bound == "string") {
     bound = commands[bound];
     if (!bound) return false;
   }
   // Ensure previous input has been read, so that the handler sees a
   // consistent view of the document
   cm.display.input.ensurePolled();
   var prevShift = cm.display.shift, done = false;
   try {
     if (isReadOnly(cm)) cm.state.suppressEdits = true;
     if (dropShift) cm.display.shift = false;
     done = bound(cm) != Pass;
   } finally {
     cm.display.shift = prevShift;
     cm.state.suppressEdits = false;
   }
   return done;
 }
 function lookupKeyForEditor(cm, name, handle) {
   for (var i = 0; i < cm.state.keyMaps.length; i++) {
     var result = lookupKey(name, cm.state.keyMaps[i], handle, cm);
     if (result) return result;
   }
   return (cm.options.extraKeys && lookupKey(name, cm.options.extraKeys, handle, cm))
     || lookupKey(name, cm.options.keyMap, handle, cm);
 }
 var stopSeq = new Delayed;
 function dispatchKey(cm, name, e, handle) {
   var seq = cm.state.keySeq;
   if (seq) {
     if (isModifierKey(name)) return "handled";
     stopSeq.set(50, function() {
       if (cm.state.keySeq == seq) {
         cm.state.keySeq = null;
         cm.display.input.reset();
       }
     });
     name = seq + " " + name;
   }
   var result = lookupKeyForEditor(cm, name, handle);
   if (result == "multi")
     cm.state.keySeq = name;
   if (result == "handled")
     signalLater(cm, "keyHandled", cm, name, e);
   if (result == "handled" || result == "multi") {
     e_preventDefault(e);
     restartBlink(cm);
   }
   if (seq && !result && /\'$/.test(name)) {
     e_preventDefault(e);
     return true;
   }
   return !!result;
 }
 // Handle a key from the keydown event.
 function handleKeyBinding(cm, e) {
   var name = keyName(e, true);
   if (!name) return false;
   if (e.shiftKey && !cm.state.keySeq) {
     // First try to resolve full name (including 'Shift-'). Failing
     // that, see if there is a cursor-motion command (starting with
     // 'go') bound to the keyname without 'Shift-'.
     return dispatchKey(cm, "Shift-" + name, e, function(b) {return doHandleBinding(cm, b, true);})
         || dispatchKey(cm, name, e, function(b) {
              if (typeof b == "string" ? /^go[A-Z]/.test(b) : b.motion)
                return doHandleBinding(cm, b);
            });
   } else {
     return dispatchKey(cm, name, e, function(b) { return doHandleBinding(cm, b); });
   }
 }
 // Handle a key from the keypress event
 function handleCharBinding(cm, e, ch) {
   return dispatchKey(cm, "'" + ch + "'", e,
                      function(b) { return doHandleBinding(cm, b, true); });
 }
 var lastStoppedKey = null;
 function onKeyDown(e) {
   var cm = this;
   cm.curOp.focus = activeElt();
   if (signalDOMEvent(cm, e)) return;
   // IE does strange things with escape.
   if (ie && ie_version < 11 && e.keyCode == 27) e.returnValue = false;
   var code = e.keyCode;
   cm.display.shift = code == 16 || e.shiftKey;
   var handled = handleKeyBinding(cm, e);
   if (presto) {
     lastStoppedKey = handled ? code : null;
     // Opera has no cut event... we try to at least catch the key combo
     if (!handled && code == 88 && !hasCopyEvent && (mac ? e.metaKey : e.ctrlKey))
       cm.replaceSelection("", null, "cut");
   }
   // Turn mouse into crosshair when Alt is held on Mac.
   if (code == 18 && !/\bCodeMirror-crosshair\b/.test(cm.display.lineDiv.className))
     showCrossHair(cm);
 }
 function showCrossHair(cm) {
   var lineDiv = cm.display.lineDiv;
   addClass(lineDiv, "CodeMirror-crosshair");
   function up(e) {
     if (e.keyCode == 18 || !e.altKey) {
       rmClass(lineDiv, "CodeMirror-crosshair");
       off(document, "keyup", up);
       off(document, "mouseover", up);
     }
   }
   on(document, "keyup", up);
   on(document, "mouseover", up);
 }
 function onKeyUp(e) {
   if (e.keyCode == 16) this.doc.sel.shift = false;
   signalDOMEvent(this, e);
 }
 function onKeyPress(e) {
   var cm = this;
   if (eventInWidget(cm.display, e) || signalDOMEvent(cm, e) || e.ctrlKey && !e.altKey || mac && e.metaKey) return;
   var keyCode = e.keyCode, charCode = e.charCode;
   if (presto && keyCode == lastStoppedKey) {lastStoppedKey = null; e_preventDefault(e); return;}
   if ((presto && (!e.which || e.which < 10)) && handleKeyBinding(cm, e)) return;
   var ch = String.fromCharCode(charCode == null ? keyCode : charCode);
   if (handleCharBinding(cm, e, ch)) return;
   cm.display.input.onKeyPress(e);
 }
 // FOCUS/BLUR EVENTS
 function delayBlurEvent(cm) {
   cm.state.delayingBlurEvent = true;
   setTimeout(function() {
     if (cm.state.delayingBlurEvent) {
       cm.state.delayingBlurEvent = false;
       onBlur(cm);
     }
   }, 100);
 }
 function onFocus(cm) {
   if (cm.state.delayingBlurEvent) cm.state.delayingBlurEvent = false;
   if (cm.options.readOnly == "nocursor") return;
   if (!cm.state.focused) {
     signal(cm, "focus", cm);
     cm.state.focused = true;
     addClass(cm.display.wrapper, "CodeMirror-focused");
     // This test prevents this from firing when a context
     // menu is closed (since the input reset would kill the
     // select-all detection hack)
     if (!cm.curOp && cm.display.selForContextMenu != cm.doc.sel) {
       cm.display.input.reset();
       if (webkit) setTimeout(function() { cm.display.input.reset(true); }, 20); // Issue #1730
     }
     cm.display.input.receivedFocus();
   }
   restartBlink(cm);
 }
 function onBlur(cm) {
   if (cm.state.delayingBlurEvent) return;
   if (cm.state.focused) {
     signal(cm, "blur", cm);
     cm.state.focused = false;
     rmClass(cm.display.wrapper, "CodeMirror-focused");
   }
   clearInterval(cm.display.blinker);
   setTimeout(function() {if (!cm.state.focused) cm.display.shift = false;}, 150);
 }
 // CONTEXT MENU HANDLING
 // To make the context menu work, we need to briefly unhide the
 // textarea (making it as unobtrusive as possible) to let the
 // right-click take effect on it.
 function onContextMenu(cm, e) {
   if (eventInWidget(cm.display, e) || contextMenuInGutter(cm, e)) return;
   cm.display.input.onContextMenu(e);
 }
 function contextMenuInGutter(cm, e) {
   if (!hasHandler(cm, "gutterContextMenu")) return false;
   return gutterEvent(cm, e, "gutterContextMenu", false, signal);
 }
 // UPDATING
 // Compute the position of the end of a change (its 'to' property
 // refers to the pre-change end).
 var changeEnd = CodeMirror.changeEnd = function(change) {
   if (!change.text) return change.to;
   return Pos(change.from.line + change.text.length - 1,
              lst(change.text).length + (change.text.length == 1 ? change.from.ch : 0));
 };
 // Adjust a position to refer to the post-change position of the
 // same text, or the end of the change if the change covers it.
 function adjustForChange(pos, change) {
   if (cmp(pos, change.from) < 0) return pos;
   if (cmp(pos, change.to) <= 0) return changeEnd(change);
   var line = pos.line + change.text.length - (change.to.line - change.from.line) - 1, ch = pos.ch;
   if (pos.line == change.to.line) ch += changeEnd(change).ch - change.to.ch;
   return Pos(line, ch);
 }
 function computeSelAfterChange(doc, change) {
   var out = [];
   for (var i = 0; i < doc.sel.ranges.length; i++) {
     var range = doc.sel.ranges[i];
     out.push(new Range(adjustForChange(range.anchor, change),
                        adjustForChange(range.head, change)));
   }
   return normalizeSelection(out, doc.sel.primIndex);
 }
 function offsetPos(pos, old, nw) {
   if (pos.line == old.line)
     return Pos(nw.line, pos.ch - old.ch + nw.ch);
   else
     return Pos(nw.line + (pos.line - old.line), pos.ch);
 }
 // Used by replaceSelections to allow moving the selection to the
 // start or around the replaced test. Hint may be "start" or "around".
 function computeReplacedSel(doc, changes, hint) {
   var out = [];
   var oldPrev = Pos(doc.first, 0), newPrev = oldPrev;
   for (var i = 0; i < changes.length; i++) {
     var change = changes[i];
     var from = offsetPos(change.from, oldPrev, newPrev);
     var to = offsetPos(changeEnd(change), oldPrev, newPrev);
     oldPrev = change.to;
     newPrev = to;
     if (hint == "around") {
       var range = doc.sel.ranges[i], inv = cmp(range.head, range.anchor) < 0;
       out[i] = new Range(inv ? to : from, inv ? from : to);
     } else {
       out[i] = new Range(from, from);
     }
   }
   return new Selection(out, doc.sel.primIndex);
 }
 // Allow "beforeChange" event handlers to influence a change
 function filterChange(doc, change, update) {
   var obj = {
     canceled: false,
     from: change.from,
     to: change.to,
     text: change.text,
     origin: change.origin,
     cancel: function() { this.canceled = true; }
   };
   if (update) obj.update = function(from, to, text, origin) {
     if (from) this.from = clipPos(doc, from);
     if (to) this.to = clipPos(doc, to);
     if (text) this.text = text;
     if (origin !== undefined) this.origin = origin;
   };
   signal(doc, "beforeChange", doc, obj);
   if (doc.cm) signal(doc.cm, "beforeChange", doc.cm, obj);
   if (obj.canceled) return null;
   return {from: obj.from, to: obj.to, text: obj.text, origin: obj.origin};
 }
 // Apply a change to a document, and add it to the document's
 // history, and propagating it to all linked documents.
 function makeChange(doc, change, ignoreReadOnly) {
   if (doc.cm) {
     if (!doc.cm.curOp) return operation(doc.cm, makeChange)(doc, change, ignoreReadOnly);
     if (doc.cm.state.suppressEdits) return;
   }
   if (hasHandler(doc, "beforeChange") || doc.cm && hasHandler(doc.cm, "beforeChange")) {
     change = filterChange(doc, change, true);
     if (!change) return;
   }
   // Possibly split or suppress the update based on the presence
   // of read-only spans in its range.
   var split = sawReadOnlySpans && !ignoreReadOnly && removeReadOnlyRanges(doc, change.from, change.to);
   if (split) {
     for (var i = split.length - 1; i >= 0; --i)
       makeChangeInner(doc, {from: split[i].from, to: split[i].to, text: i ? [""] : change.text});
   } else {
     makeChangeInner(doc, change);
   }
 }
 function makeChangeInner(doc, change) {
   if (change.text.length == 1 && change.text[0] == "" && cmp(change.from, change.to) == 0) return;
   var selAfter = computeSelAfterChange(doc, change);
   addChangeToHistory(doc, change, selAfter, doc.cm ? doc.cm.curOp.id : NaN);
   makeChangeSingleDoc(doc, change, selAfter, stretchSpansOverChange(doc, change));
   var rebased = [];
   linkedDocs(doc, function(doc, sharedHist) {
     if (!sharedHist && indexOf(rebased, doc.history) == -1) {
       rebaseHist(doc.history, change);
       rebased.push(doc.history);
     }
     makeChangeSingleDoc(doc, change, null, stretchSpansOverChange(doc, change));
   });
 }
 // Revert a change stored in a document's history.
 function makeChangeFromHistory(doc, type, allowSelectionOnly) {
   if (doc.cm && doc.cm.state.suppressEdits) return;
   var hist = doc.history, event, selAfter = doc.sel;
   var source = type == "undo" ? hist.done : hist.undone, dest = type == "undo" ? hist.undone : hist.done;
   // Verify that there is a useable event (so that ctrl-z won't
   // needlessly clear selection events)
   for (var i = 0; i < source.length; i++) {
     event = source[i];
     if (allowSelectionOnly ? event.ranges && !event.equals(doc.sel) : !event.ranges)
       break;
   }
   if (i == source.length) return;
   hist.lastOrigin = hist.lastSelOrigin = null;
   for (;;) {
     event = source.pop();
     if (event.ranges) {
       pushSelectionToHistory(event, dest);
       if (allowSelectionOnly && !event.equals(doc.sel)) {
         setSelection(doc, event, {clearRedo: false});
         return;
       }
       selAfter = event;
     }
     else break;
   }
   // Build up a reverse change object to add to the opposite history
   // stack (redo when undoing, and vice versa).
   var antiChanges = [];
   pushSelectionToHistory(selAfter, dest);
   dest.push({changes: antiChanges, generation: hist.generation});
   hist.generation = event.generation || ++hist.maxGeneration;
   var filter = hasHandler(doc, "beforeChange") || doc.cm && hasHandler(doc.cm, "beforeChange");
   for (var i = event.changes.length - 1; i >= 0; --i) {
     var change = event.changes[i];
     change.origin = type;
     if (filter && !filterChange(doc, change, false)) {
       source.length = 0;
       return;
     }
     antiChanges.push(historyChangeFromChange(doc, change));
     var after = i ? computeSelAfterChange(doc, change) : lst(source);
     makeChangeSingleDoc(doc, change, after, mergeOldSpans(doc, change));
     if (!i && doc.cm) doc.cm.scrollIntoView({from: change.from, to: changeEnd(change)});
     var rebased = [];
     // Propagate to the linked documents
     linkedDocs(doc, function(doc, sharedHist) {
       if (!sharedHist && indexOf(rebased, doc.history) == -1) {
         rebaseHist(doc.history, change);
         rebased.push(doc.history);
       }
       makeChangeSingleDoc(doc, change, null, mergeOldSpans(doc, change));
     });
   }
 }
 // Sub-views need their line numbers shifted when text is added
 // above or below them in the parent document.
 function shiftDoc(doc, distance) {
   if (distance == 0) return;
   doc.first += distance;
   doc.sel = new Selection(map(doc.sel.ranges, function(range) {
     return new Range(Pos(range.anchor.line + distance, range.anchor.ch),
                      Pos(range.head.line + distance, range.head.ch));
   }), doc.sel.primIndex);
   if (doc.cm) {
     regChange(doc.cm, doc.first, doc.first - distance, distance);
     for (var d = doc.cm.display, l = d.viewFrom; l < d.viewTo; l++)
       regLineChange(doc.cm, l, "gutter");
   }
 }
 // More lower-level change function, handling only a single document
 // (not linked ones).
 function makeChangeSingleDoc(doc, change, selAfter, spans) {
   if (doc.cm && !doc.cm.curOp)
     return operation(doc.cm, makeChangeSingleDoc)(doc, change, selAfter, spans);
   if (change.to.line < doc.first) {
     shiftDoc(doc, change.text.length - 1 - (change.to.line - change.from.line));
     return;
   }
   if (change.from.line > doc.lastLine()) return;
   // Clip the change to the size of this doc
   if (change.from.line < doc.first) {
     var shift = change.text.length - 1 - (doc.first - change.from.line);
     shiftDoc(doc, shift);
     change = {from: Pos(doc.first, 0), to: Pos(change.to.line + shift, change.to.ch),
               text: [lst(change.text)], origin: change.origin};
   }
   var last = doc.lastLine();
   if (change.to.line > last) {
     change = {from: change.from, to: Pos(last, getLine(doc, last).text.length),
               text: [change.text[0]], origin: change.origin};
   }
   change.removed = getBetween(doc, change.from, change.to);
   if (!selAfter) selAfter = computeSelAfterChange(doc, change);
   if (doc.cm) makeChangeSingleDocInEditor(doc.cm, change, spans);
   else updateDoc(doc, change, spans);
   setSelectionNoUndo(doc, selAfter, sel_dontScroll);
 }
 // Handle the interaction of a change to a document with the editor
 // that this document is part of.
 function makeChangeSingleDocInEditor(cm, change, spans) {
   var doc = cm.doc, display = cm.display, from = change.from, to = change.to;
   var recomputeMaxLength = false, checkWidthStart = from.line;
   if (!cm.options.lineWrapping) {
     checkWidthStart = lineNo(visualLine(getLine(doc, from.line)));
     doc.iter(checkWidthStart, to.line + 1, function(line) {
       if (line == display.maxLine) {
         recomputeMaxLength = true;
         return true;
       }
     });
   }
   if (doc.sel.contains(change.from, change.to) > -1)
     signalCursorActivity(cm);
   updateDoc(doc, change, spans, estimateHeight(cm));
   if (!cm.options.lineWrapping) {
     doc.iter(checkWidthStart, from.line + change.text.length, function(line) {
       var len = lineLength(line);
       if (len > display.maxLineLength) {
         display.maxLine = line;
         display.maxLineLength = len;
         display.maxLineChanged = true;
         recomputeMaxLength = false;
       }
     });
     if (recomputeMaxLength) cm.curOp.updateMaxLine = true;
   }
   // Adjust frontier, schedule worker
   doc.frontier = Math.min(doc.frontier, from.line);
   startWorker(cm, 400);
   var lendiff = change.text.length - (to.line - from.line) - 1;
   // Remember that these lines changed, for updating the display
   if (change.full)
     regChange(cm);
   else if (from.line == to.line && change.text.length == 1 && !isWholeLineUpdate(cm.doc, change))
     regLineChange(cm, from.line, "text");
   else
     regChange(cm, from.line, to.line + 1, lendiff);
   var changesHandler = hasHandler(cm, "changes"), changeHandler = hasHandler(cm, "change");
   if (changeHandler || changesHandler) {
     var obj = {
       from: from, to: to,
       text: change.text,
       removed: change.removed,
       origin: change.origin
     };
     if (changeHandler) signalLater(cm, "change", cm, obj);
     if (changesHandler) (cm.curOp.changeObjs || (cm.curOp.changeObjs = [])).push(obj);
   }
   cm.display.selForContextMenu = null;
 }
 function replaceRange(doc, code, from, to, origin) {
   if (!to) to = from;
   if (cmp(to, from) < 0) { var tmp = to; to = from; from = tmp; }
   if (typeof code == "string") code = doc.splitLines(code);
   makeChange(doc, {from: from, to: to, text: code, origin: origin});
 }
 // SCROLLING THINGS INTO VIEW
 // If an editor sits on the top or bottom of the window, partially
 // scrolled out of view, this ensures that the cursor is visible.
 function maybeScrollWindow(cm, coords) {
   if (signalDOMEvent(cm, "scrollCursorIntoView")) return;
   var display = cm.display, box = display.sizer.getBoundingClientRect(), doScroll = null;
   if (coords.top + box.top < 0) doScroll = true;
   else if (coords.bottom + box.top > (window.innerHeight || document.documentElement.clientHeight)) doScroll = false;
   if (doScroll != null && !phantom) {
     var scrollNode = elt("div", "\u200b", null, "position: absolute; top: " +
                          (coords.top - display.viewOffset - paddingTop(cm.display)) + "px; height: " +
                          (coords.bottom - coords.top + scrollGap(cm) + display.barHeight) + "px; left: " +
                          coords.left + "px; width: 2px;");
     cm.display.lineSpace.appendChild(scrollNode);
     scrollNode.scrollIntoView(doScroll);
     cm.display.lineSpace.removeChild(scrollNode);
   }
 }
 // Scroll a given position into view (immediately), verifying that
 // it actually became visible (as line heights are accurately
 // measured, the position of something may 'drift' during drawing).
 function scrollPosIntoView(cm, pos, end, margin) {
   if (margin == null) margin = 0;
   for (var limit = 0; limit < 5; limit++) {
     var changed = false, coords = cursorCoords(cm, pos);
     var endCoords = !end || end == pos ? coords : cursorCoords(cm, end);
     var scrollPos = calculateScrollPos(cm, Math.min(coords.left, endCoords.left),
                                        Math.min(coords.top, endCoords.top) - margin,
                                        Math.max(coords.left, endCoords.left),
                                        Math.max(coords.bottom, endCoords.bottom) + margin);
     var startTop = cm.doc.scrollTop, startLeft = cm.doc.scrollLeft;
     if (scrollPos.scrollTop != null) {
       setScrollTop(cm, scrollPos.scrollTop);
       if (Math.abs(cm.doc.scrollTop - startTop) > 1) changed = true;
     }
     if (scrollPos.scrollLeft != null) {
       setScrollLeft(cm, scrollPos.scrollLeft);
       if (Math.abs(cm.doc.scrollLeft - startLeft) > 1) changed = true;
     }
     if (!changed) break;
   }
   return coords;
 }
 // Scroll a given set of coordinates into view (immediately).
 function scrollIntoView(cm, x1, y1, x2, y2) {
   var scrollPos = calculateScrollPos(cm, x1, y1, x2, y2);
   if (scrollPos.scrollTop != null) setScrollTop(cm, scrollPos.scrollTop);
   if (scrollPos.scrollLeft != null) setScrollLeft(cm, scrollPos.scrollLeft);
 }
 // Calculate a new scroll position needed to scroll the given
 // rectangle into view. Returns an object with scrollTop and
 // scrollLeft properties. When these are undefined, the
 // vertical/horizontal position does not need to be adjusted.
 function calculateScrollPos(cm, x1, y1, x2, y2) {
   var display = cm.display, snapMargin = textHeight(cm.display);
   if (y1 < 0) y1 = 0;
   var screentop = cm.curOp && cm.curOp.scrollTop != null ? cm.curOp.scrollTop : display.scroller.scrollTop;
   var screen = displayHeight(cm), result = {};
   if (y2 - y1 > screen) y2 = y1 + screen;
   var docBottom = cm.doc.height + paddingVert(display);
   var atTop = y1 < snapMargin, atBottom = y2 > docBottom - snapMargin;
   if (y1 < screentop) {
     result.scrollTop = atTop ? 0 : y1;
   } else if (y2 > screentop + screen) {
     var newTop = Math.min(y1, (atBottom ? docBottom : y2) - screen);
     if (newTop != screentop) result.scrollTop = newTop;
   }
   var screenleft = cm.curOp && cm.curOp.scrollLeft != null ? cm.curOp.scrollLeft : display.scroller.scrollLeft;
   var screenw = displayWidth(cm) - (cm.options.fixedGutter ? display.gutters.offsetWidth : 0);
   var tooWide = x2 - x1 > screenw;
   if (tooWide) x2 = x1 + screenw;
   if (x1 < 10)
     result.scrollLeft = 0;
   else if (x1 < screenleft)
     result.scrollLeft = Math.max(0, x1 - (tooWide ? 0 : 10));
   else if (x2 > screenw + screenleft - 3)
     result.scrollLeft = x2 + (tooWide ? 0 : 10) - screenw;
   return result;
 }
 // Store a relative adjustment to the scroll position in the current
 // operation (to be applied when the operation finishes).
 function addToScrollPos(cm, left, top) {
   if (left != null || top != null) resolveScrollToPos(cm);
   if (left != null)
     cm.curOp.scrollLeft = (cm.curOp.scrollLeft == null ? cm.doc.scrollLeft : cm.curOp.scrollLeft) + left;
   if (top != null)
     cm.curOp.scrollTop = (cm.curOp.scrollTop == null ? cm.doc.scrollTop : cm.curOp.scrollTop) + top;
 }
 // Make sure that at the end of the operation the current cursor is
 // shown.
 function ensureCursorVisible(cm) {
   resolveScrollToPos(cm);
   var cur = cm.getCursor(), from = cur, to = cur;
   if (!cm.options.lineWrapping) {
     from = cur.ch ? Pos(cur.line, cur.ch - 1) : cur;
     to = Pos(cur.line, cur.ch + 1);
   }
   cm.curOp.scrollToPos = {from: from, to: to, margin: cm.options.cursorScrollMargin, isCursor: true};
 }
 // When an operation has its scrollToPos property set, and another
 // scroll action is applied before the end of the operation, this
 // 'simulates' scrolling that position into view in a cheap way, so
 // that the effect of intermediate scroll commands is not ignored.
 function resolveScrollToPos(cm) {
   var range = cm.curOp.scrollToPos;
   if (range) {
     cm.curOp.scrollToPos = null;
     var from = estimateCoords(cm, range.from), to = estimateCoords(cm, range.to);
     var sPos = calculateScrollPos(cm, Math.min(from.left, to.left),
                                   Math.min(from.top, to.top) - range.margin,
                                   Math.max(from.right, to.right),
                                   Math.max(from.bottom, to.bottom) + range.margin);
     cm.scrollTo(sPos.scrollLeft, sPos.scrollTop);
   }
 }
 // API UTILITIES
 // Indent the given line. The how parameter can be "smart",
 // "add"/null, "subtract", or "prev". When aggressive is false
 // (typically set to true for forced single-line indents), empty
 // lines are not indented, and places where the mode returns Pass
 // are left alone.
 function indentLine(cm, n, how, aggressive) {
   var doc = cm.doc, state;
   if (how == null) how = "add";
   if (how == "smart") {
     // Fall back to "prev" when the mode doesn't have an indentation
     // method.
     if (!doc.mode.indent) how = "prev";
     else state = getStateBefore(cm, n);
   }
   var tabSize = cm.options.tabSize;
   var line = getLine(doc, n), curSpace = countColumn(line.text, null, tabSize);
   if (line.stateAfter) line.stateAfter = null;
   var curSpaceString = line.text.match(/^\s*/)[0], indentation;
   if (!aggressive && !/\S/.test(line.text)) {
     indentation = 0;
     how = "not";
   } else if (how == "smart") {
     indentation = doc.mode.indent(state, line.text.slice(curSpaceString.length), line.text);
     if (indentation == Pass || indentation > 150) {
       if (!aggressive) return;
       how = "prev";
     }
   }
   if (how == "prev") {
     if (n > doc.first) indentation = countColumn(getLine(doc, n-1).text, null, tabSize);
     else indentation = 0;
   } else if (how == "add") {
     indentation = curSpace + cm.options.indentUnit;
   } else if (how == "subtract") {
     indentation = curSpace - cm.options.indentUnit;
   } else if (typeof how == "number") {
     indentation = curSpace + how;
   }
   indentation = Math.max(0, indentation);
   var indentString = "", pos = 0;
   if (cm.options.indentWithTabs)
     for (var i = Math.floor(indentation / tabSize); i; --i) {pos += tabSize; indentString += "\t";}
   if (pos < indentation) indentString += spaceStr(indentation - pos);
   if (indentString != curSpaceString) {
     replaceRange(doc, indentString, Pos(n, 0), Pos(n, curSpaceString.length), "+input");
     line.stateAfter = null;
     return true;
   } else {
     // Ensure that, if the cursor was in the whitespace at the start
     // of the line, it is moved to the end of that space.
     for (var i = 0; i < doc.sel.ranges.length; i++) {
       var range = doc.sel.ranges[i];
       if (range.head.line == n && range.head.ch < curSpaceString.length) {
         var pos = Pos(n, curSpaceString.length);
         replaceOneSelection(doc, i, new Range(pos, pos));
         break;
       }
     }
   }
 }
 // Utility for applying a change to a line by handle or number,
 // returning the number and optionally registering the line as
 // changed.
 function changeLine(doc, handle, changeType, op) {
   var no = handle, line = handle;
   if (typeof handle == "number") line = getLine(doc, clipLine(doc, handle));
   else no = lineNo(handle);
   if (no == null) return null;
   if (op(line, no) && doc.cm) regLineChange(doc.cm, no, changeType);
   return line;
 }
 // Helper for deleting text near the selection(s), used to implement
 // backspace, delete, and similar functionality.
 function deleteNearSelection(cm, compute) {
   var ranges = cm.doc.sel.ranges, kill = [];
   // Build up a set of ranges to kill first, merging overlapping
   // ranges.
   for (var i = 0; i < ranges.length; i++) {
     var toKill = compute(ranges[i]);
     while (kill.length && cmp(toKill.from, lst(kill).to) <= 0) {
       var replaced = kill.pop();
       if (cmp(replaced.from, toKill.from) < 0) {
         toKill.from = replaced.from;
         break;
       }
     }
     kill.push(toKill);
   }
   // Next, remove those actual ranges.
   runInOp(cm, function() {
     for (var i = kill.length - 1; i >= 0; i--)
       replaceRange(cm.doc, "", kill[i].from, kill[i].to, "+delete");
     ensureCursorVisible(cm);
   });
 }
 // Used for horizontal relative motion. Dir is -1 or 1 (left or
 // right), unit can be "char", "column" (like char, but doesn't
 // cross line boundaries), "word" (across next word), or "group" (to
 // the start of next group of word or non-word-non-whitespace
 // chars). The visually param controls whether, in right-to-left
 // text, direction 1 means to move towards the next index in the
 // string, or towards the character to the right of the current
 // position. The resulting position will have a hitSide=true
 // property if it reached the end of the document.
 function findPosH(doc, pos, dir, unit, visually) {
   var line = pos.line, ch = pos.ch, origDir = dir;
   var lineObj = getLine(doc, line);
   var possible = true;
   function findNextLine() {
     var l = line + dir;
     if (l < doc.first || l >= doc.first + doc.size) return (possible = false);
     line = l;
     return lineObj = getLine(doc, l);
   }
   function moveOnce(boundToLine) {
     var next = (visually ? moveVisually : moveLogically)(lineObj, ch, dir, true);
     if (next == null) {
       if (!boundToLine && findNextLine()) {
         if (visually) ch = (dir < 0 ? lineRight : lineLeft)(lineObj);
         else ch = dir < 0 ? lineObj.text.length : 0;
       } else return (possible = false);
     } else ch = next;
     return true;
   }
   if (unit == "char") moveOnce();
   else if (unit == "column") moveOnce(true);
   else if (unit == "word" || unit == "group") {
     var sawType = null, group = unit == "group";
     var helper = doc.cm && doc.cm.getHelper(pos, "wordChars");
     for (var first = true;; first = false) {
       if (dir < 0 && !moveOnce(!first)) break;
       var cur = lineObj.text.charAt(ch) || "\n";
       var type = isWordChar(cur, helper) ? "w"
         : group && cur == "\n" ? "n"
         : !group || /\s/.test(cur) ? null
         : "p";
       if (group && !first && !type) type = "s";
       if (sawType && sawType != type) {
         if (dir < 0) {dir = 1; moveOnce();}
         break;
       }
       if (type) sawType = type;
       if (dir > 0 && !moveOnce(!first)) break;
     }
   }
   var result = skipAtomic(doc, Pos(line, ch), origDir, true);
   if (!possible) result.hitSide = true;
   return result;
 }
 // For relative vertical movement. Dir may be -1 or 1. Unit can be
 // "page" or "line". The resulting position will have a hitSide=true
 // property if it reached the end of the document.
 function findPosV(cm, pos, dir, unit) {
   var doc = cm.doc, x = pos.left, y;
   if (unit == "page") {
     var pageSize = Math.min(cm.display.wrapper.clientHeight, window.innerHeight || document.documentElement.clientHeight);
     y = pos.top + dir * (pageSize - (dir < 0 ? 1.5 : .5) * textHeight(cm.display));
   } else if (unit == "line") {
     y = dir > 0 ? pos.bottom + 3 : pos.top - 3;
   }
   for (;;) {
     var target = coordsChar(cm, x, y);
     if (!target.outside) break;
     if (dir < 0 ? y <= 0 : y >= doc.height) { target.hitSide = true; break; }
     y += dir * 5;
   }
   return target;
 }
 // EDITOR METHODS
 // The publicly visible API. Note that methodOp(f) means
 // 'wrap f in an operation, performed on its `this` parameter'.
 // This is not the complete set of editor methods. Most of the
 // methods defined on the Doc type are also injected into
 // CodeMirror.prototype, for backwards compatibility and
 // convenience.
 CodeMirror.prototype = {
   constructor: CodeMirror,
   focus: function(){window.focus(); this.display.input.focus();},
   setOption: function(option, value) {
     var options = this.options, old = options[option];
     if (options[option] == value && option != "mode") return;
     options[option] = value;
     if (optionHandlers.hasOwnProperty(option))
       operation(this, optionHandlers[option])(this, value, old);
   },
   getOption: function(option) {return this.options[option];},
   getDoc: function() {return this.doc;},
   addKeyMap: function(map, bottom) {
     this.state.keyMaps[bottom ? "push" : "unshift"](getKeyMap(map));
   },
   removeKeyMap: function(map) {
     var maps = this.state.keyMaps;
     for (var i = 0; i < maps.length; ++i)
       if (maps[i] == map || maps[i].name == map) {
         maps.splice(i, 1);
         return true;
       }
   },
   addOverlay: methodOp(function(spec, options) {
     var mode = spec.token ? spec : CodeMirror.getMode(this.options, spec);
     if (mode.startState) throw new Error("Overlays may not be stateful.");
     this.state.overlays.push({mode: mode, modeSpec: spec, opaque: options && options.opaque});
     this.state.modeGen++;
     regChange(this);
   }),
   removeOverlay: methodOp(function(spec) {
     var overlays = this.state.overlays;
     for (var i = 0; i < overlays.length; ++i) {
       var cur = overlays[i].modeSpec;
       if (cur == spec || typeof spec == "string" && cur.name == spec) {
         overlays.splice(i, 1);
         this.state.modeGen++;
         regChange(this);
         return;
       }
     }
   }),
   indentLine: methodOp(function(n, dir, aggressive) {
     if (typeof dir != "string" && typeof dir != "number") {
       if (dir == null) dir = this.options.smartIndent ? "smart" : "prev";
       else dir = dir ? "add" : "subtract";
     }
     if (isLine(this.doc, n)) indentLine(this, n, dir, aggressive);
   }),
   indentSelection: methodOp(function(how) {
     var ranges = this.doc.sel.ranges, end = -1;
     for (var i = 0; i < ranges.length; i++) {
       var range = ranges[i];
       if (!range.empty()) {
         var from = range.from(), to = range.to();
         var start = Math.max(end, from.line);
         end = Math.min(this.lastLine(), to.line - (to.ch ? 0 : 1)) + 1;
         for (var j = start; j < end; ++j)
           indentLine(this, j, how);
         var newRanges = this.doc.sel.ranges;
         if (from.ch == 0 && ranges.length == newRanges.length && newRanges[i].from().ch > 0)
           replaceOneSelection(this.doc, i, new Range(from, newRanges[i].to()), sel_dontScroll);
       } else if (range.head.line > end) {
         indentLine(this, range.head.line, how, true);
         end = range.head.line;
         if (i == this.doc.sel.primIndex) ensureCursorVisible(this);
       }
     }
   }),
   // Fetch the parser token for a given character. Useful for hacks
   // that want to inspect the mode state (say, for completion).
   getTokenAt: function(pos, precise) {
     return takeToken(this, pos, precise);
   },
   getLineTokens: function(line, precise) {
     return takeToken(this, Pos(line), precise, true);
   },
   getTokenTypeAt: function(pos) {
     pos = clipPos(this.doc, pos);
     var styles = getLineStyles(this, getLine(this.doc, pos.line));
     var before = 0, after = (styles.length - 1) / 2, ch = pos.ch;
     var type;
     if (ch == 0) type = styles[2];
     else for (;;) {
       var mid = (before + after) >> 1;
       if ((mid ? styles[mid * 2 - 1] : 0) >= ch) after = mid;
       else if (styles[mid * 2 + 1] < ch) before = mid + 1;
       else { type = styles[mid * 2 + 2]; break; }
     }
     var cut = type ? type.indexOf("cm-overlay ") : -1;
     return cut < 0 ? type : cut == 0 ? null : type.slice(0, cut - 1);
   },
   getModeAt: function(pos) {
     var mode = this.doc.mode;
     if (!mode.innerMode) return mode;
     return CodeMirror.innerMode(mode, this.getTokenAt(pos).state).mode;
   },
   getHelper: function(pos, type) {
     return this.getHelpers(pos, type)[0];
   },
   getHelpers: function(pos, type) {
     var found = [];
     if (!helpers.hasOwnProperty(type)) return found;
     var help = helpers[type], mode = this.getModeAt(pos);
     if (typeof mode[type] == "string") {
       if (help[mode[type]]) found.push(help[mode[type]]);
     } else if (mode[type]) {
       for (var i = 0; i < mode[type].length; i++) {
         var val = help[mode[type][i]];
         if (val) found.push(val);
       }
     } else if (mode.helperType && help[mode.helperType]) {
       found.push(help[mode.helperType]);
     } else if (help[mode.name]) {
       found.push(help[mode.name]);
     }
     for (var i = 0; i < help._global.length; i++) {
       var cur = help._global[i];
       if (cur.pred(mode, this) && indexOf(found, cur.val) == -1)
         found.push(cur.val);
     }
     return found;
   },
   getStateAfter: function(line, precise) {
     var doc = this.doc;
     line = clipLine(doc, line == null ? doc.first + doc.size - 1: line);
     return getStateBefore(this, line + 1, precise);
   },
   cursorCoords: function(start, mode) {
     var pos, range = this.doc.sel.primary();
     if (start == null) pos = range.head;
     else if (typeof start == "object") pos = clipPos(this.doc, start);
     else pos = start ? range.from() : range.to();
     return cursorCoords(this, pos, mode || "page");
   },
   charCoords: function(pos, mode) {
     return charCoords(this, clipPos(this.doc, pos), mode || "page");
   },
   coordsChar: function(coords, mode) {
     coords = fromCoordSystem(this, coords, mode || "page");
     return coordsChar(this, coords.left, coords.top);
   },
   lineAtHeight: function(height, mode) {
     height = fromCoordSystem(this, {top: height, left: 0}, mode || "page").top;
     return lineAtHeight(this.doc, height + this.display.viewOffset);
   },
   heightAtLine: function(line, mode) {
     var end = false, lineObj;
     if (typeof line == "number") {
       var last = this.doc.first + this.doc.size - 1;
       if (line < this.doc.first) line = this.doc.first;
       else if (line > last) { line = last; end = true; }
       lineObj = getLine(this.doc, line);
     } else {
       lineObj = line;
     }
     return intoCoordSystem(this, lineObj, {top: 0, left: 0}, mode || "page").top +
       (end ? this.doc.height - heightAtLine(lineObj) : 0);
   },
   defaultTextHeight: function() { return textHeight(this.display); },
   defaultCharWidth: function() { return charWidth(this.display); },
   setGutterMarker: methodOp(function(line, gutterID, value) {
     return changeLine(this.doc, line, "gutter", function(line) {
       var markers = line.gutterMarkers || (line.gutterMarkers = {});
       markers[gutterID] = value;
       if (!value && isEmpty(markers)) line.gutterMarkers = null;
       return true;
     });
   }),
   clearGutter: methodOp(function(gutterID) {
     var cm = this, doc = cm.doc, i = doc.first;
     doc.iter(function(line) {
       if (line.gutterMarkers && line.gutterMarkers[gutterID]) {
         line.gutterMarkers[gutterID] = null;
         regLineChange(cm, i, "gutter");
         if (isEmpty(line.gutterMarkers)) line.gutterMarkers = null;
       }
       ++i;
     });
   }),
   lineInfo: function(line) {
     if (typeof line == "number") {
       if (!isLine(this.doc, line)) return null;
       var n = line;
       line = getLine(this.doc, line);
       if (!line) return null;
     } else {
       var n = lineNo(line);
       if (n == null) return null;
     }
     return {line: n, handle: line, text: line.text, gutterMarkers: line.gutterMarkers,
             textClass: line.textClass, bgClass: line.bgClass, wrapClass: line.wrapClass,
             widgets: line.widgets};
   },
   getViewport: function() { return {from: this.display.viewFrom, to: this.display.viewTo};},
   addWidget: function(pos, node, scroll, vert, horiz) {
     var display = this.display;
     pos = cursorCoords(this, clipPos(this.doc, pos));
     var top = pos.bottom, left = pos.left;
     node.style.position = "absolute";
     node.setAttribute("cm-ignore-events", "true");
     this.display.input.setUneditable(node);
     display.sizer.appendChild(node);
     if (vert == "over") {
       top = pos.top;
     } else if (vert == "above" || vert == "near") {
       var vspace = Math.max(display.wrapper.clientHeight, this.doc.height),
       hspace = Math.max(display.sizer.clientWidth, display.lineSpace.clientWidth);
       // Default to positioning above (if specified and possible); otherwise default to positioning below
       if ((vert == 'above' || pos.bottom + node.offsetHeight > vspace) && pos.top > node.offsetHeight)
         top = pos.top - node.offsetHeight;
       else if (pos.bottom + node.offsetHeight <= vspace)
         top = pos.bottom;
       if (left + node.offsetWidth > hspace)
         left = hspace - node.offsetWidth;
     }
     node.style.top = top + "px";
     node.style.left = node.style.right = "";
     if (horiz == "right") {
       left = display.sizer.clientWidth - node.offsetWidth;
       node.style.right = "0px";
     } else {
       if (horiz == "left") left = 0;
       else if (horiz == "middle") left = (display.sizer.clientWidth - node.offsetWidth) / 2;
       node.style.left = left + "px";
     }
     if (scroll)
       scrollIntoView(this, left, top, left + node.offsetWidth, top + node.offsetHeight);
   },
   triggerOnKeyDown: methodOp(onKeyDown),
   triggerOnKeyPress: methodOp(onKeyPress),
   triggerOnKeyUp: onKeyUp,
   execCommand: function(cmd) {
     if (commands.hasOwnProperty(cmd))
       return commands[cmd].call(null, this);
   },
   triggerElectric: methodOp(function(text) { triggerElectric(this, text); }),
   findPosH: function(from, amount, unit, visually) {
     var dir = 1;
     if (amount < 0) { dir = -1; amount = -amount; }
     for (var i = 0, cur = clipPos(this.doc, from); i < amount; ++i) {
       cur = findPosH(this.doc, cur, dir, unit, visually);
       if (cur.hitSide) break;
     }
     return cur;
   },
   moveH: methodOp(function(dir, unit) {
     var cm = this;
     cm.extendSelectionsBy(function(range) {
       if (cm.display.shift || cm.doc.extend || range.empty())
         return findPosH(cm.doc, range.head, dir, unit, cm.options.rtlMoveVisually);
       else
         return dir < 0 ? range.from() : range.to();
     }, sel_move);
   }),
   deleteH: methodOp(function(dir, unit) {
     var sel = this.doc.sel, doc = this.doc;
     if (sel.somethingSelected())
       doc.replaceSelection("", null, "+delete");
     else
       deleteNearSelection(this, function(range) {
         var other = findPosH(doc, range.head, dir, unit, false);
         return dir < 0 ? {from: other, to: range.head} : {from: range.head, to: other};
       });
   }),
   findPosV: function(from, amount, unit, goalColumn) {
     var dir = 1, x = goalColumn;
     if (amount < 0) { dir = -1; amount = -amount; }
     for (var i = 0, cur = clipPos(this.doc, from); i < amount; ++i) {
       var coords = cursorCoords(this, cur, "div");
       if (x == null) x = coords.left;
       else coords.left = x;
       cur = findPosV(this, coords, dir, unit);
       if (cur.hitSide) break;
     }
     return cur;
   },
   moveV: methodOp(function(dir, unit) {
     var cm = this, doc = this.doc, goals = [];
     var collapse = !cm.display.shift && !doc.extend && doc.sel.somethingSelected();
     doc.extendSelectionsBy(function(range) {
       if (collapse)
         return dir < 0 ? range.from() : range.to();
       var headPos = cursorCoords(cm, range.head, "div");
       if (range.goalColumn != null) headPos.left = range.goalColumn;
       goals.push(headPos.left);
       var pos = findPosV(cm, headPos, dir, unit);
       if (unit == "page" && range == doc.sel.primary())
         addToScrollPos(cm, null, charCoords(cm, pos, "div").top - headPos.top);
       return pos;
     }, sel_move);
     if (goals.length) for (var i = 0; i < doc.sel.ranges.length; i++)
       doc.sel.ranges[i].goalColumn = goals[i];
   }),
   // Find the word at the given position (as returned by coordsChar).
   findWordAt: function(pos) {
     var doc = this.doc, line = getLine(doc, pos.line).text;
     var start = pos.ch, end = pos.ch;
     if (line) {
       var helper = this.getHelper(pos, "wordChars");
       if ((pos.xRel < 0 || end == line.length) && start) --start; else ++end;
       var startChar = line.charAt(start);
       var check = isWordChar(startChar, helper)
         ? function(ch) { return isWordChar(ch, helper); }
         : /\s/.test(startChar) ? function(ch) {return /\s/.test(ch);}
         : function(ch) {return !/\s/.test(ch) && !isWordChar(ch);};
       while (start > 0 && check(line.charAt(start - 1))) --start;
       while (end < line.length && check(line.charAt(end))) ++end;
     }
     return new Range(Pos(pos.line, start), Pos(pos.line, end));
   },
   toggleOverwrite: function(value) {
     if (value != null && value == this.state.overwrite) return;
     if (this.state.overwrite = !this.state.overwrite)
       addClass(this.display.cursorDiv, "CodeMirror-overwrite");
     else
       rmClass(this.display.cursorDiv, "CodeMirror-overwrite");
     signal(this, "overwriteToggle", this, this.state.overwrite);
   },
   hasFocus: function() { return this.display.input.getField() == activeElt(); },
   scrollTo: methodOp(function(x, y) {
     if (x != null || y != null) resolveScrollToPos(this);
     if (x != null) this.curOp.scrollLeft = x;
     if (y != null) this.curOp.scrollTop = y;
   }),
   getScrollInfo: function() {
     var scroller = this.display.scroller;
     return {left: scroller.scrollLeft, top: scroller.scrollTop,
             height: scroller.scrollHeight - scrollGap(this) - this.display.barHeight,
             width: scroller.scrollWidth - scrollGap(this) - this.display.barWidth,
             clientHeight: displayHeight(this), clientWidth: displayWidth(this)};
   },
   scrollIntoView: methodOp(function(range, margin) {
     if (range == null) {
       range = {from: this.doc.sel.primary().head, to: null};
       if (margin == null) margin = this.options.cursorScrollMargin;
     } else if (typeof range == "number") {
       range = {from: Pos(range, 0), to: null};
     } else if (range.from == null) {
       range = {from: range, to: null};
     }
     if (!range.to) range.to = range.from;
     range.margin = margin || 0;
     if (range.from.line != null) {
       resolveScrollToPos(this);
       this.curOp.scrollToPos = range;
     } else {
       var sPos = calculateScrollPos(this, Math.min(range.from.left, range.to.left),
                                     Math.min(range.from.top, range.to.top) - range.margin,
                                     Math.max(range.from.right, range.to.right),
                                     Math.max(range.from.bottom, range.to.bottom) + range.margin);
       this.scrollTo(sPos.scrollLeft, sPos.scrollTop);
     }
   }),
   setSize: methodOp(function(width, height) {
     var cm = this;
     function interpret(val) {
       return typeof val == "number" || /^\d+$/.test(String(val)) ? val + "px" : val;
     }
     if (width != null) cm.display.wrapper.style.width = interpret(width);
     if (height != null) cm.display.wrapper.style.height = interpret(height);
     if (cm.options.lineWrapping) clearLineMeasurementCache(this);
     var lineNo = cm.display.viewFrom;
     cm.doc.iter(lineNo, cm.display.viewTo, function(line) {
       if (line.widgets) for (var i = 0; i < line.widgets.length; i++)
         if (line.widgets[i].noHScroll) { regLineChange(cm, lineNo, "widget"); break; }
       ++lineNo;
     });
     cm.curOp.forceUpdate = true;
     signal(cm, "refresh", this);
   }),
   operation: function(f){return runInOp(this, f);},
   refresh: methodOp(function() {
     var oldHeight = this.display.cachedTextHeight;
     regChange(this);
     this.curOp.forceUpdate = true;
     clearCaches(this);
     this.scrollTo(this.doc.scrollLeft, this.doc.scrollTop);
     updateGutterSpace(this);
     if (oldHeight == null || Math.abs(oldHeight - textHeight(this.display)) > .5)
       estimateLineHeights(this);
     signal(this, "refresh", this);
   }),
   swapDoc: methodOp(function(doc) {
     var old = this.doc;
     old.cm = null;
     attachDoc(this, doc);
     clearCaches(this);
     this.display.input.reset();
     this.scrollTo(doc.scrollLeft, doc.scrollTop);
     this.curOp.forceScroll = true;
     signalLater(this, "swapDoc", this, old);
     return old;
   }),
   getInputField: function(){return this.display.input.getField();},
   getWrapperElement: function(){return this.display.wrapper;},
   getScrollerElement: function(){return this.display.scroller;},
   getGutterElement: function(){return this.display.gutters;}
 };
 eventMixin(CodeMirror);
 // OPTION DEFAULTS
 // The default configuration options.
 var defaults = CodeMirror.defaults = {};
 // Functions to run when options are changed.
 var optionHandlers = CodeMirror.optionHandlers = {};
 function option(name, deflt, handle, notOnInit) {
   CodeMirror.defaults[name] = deflt;
   if (handle) optionHandlers[name] =
     notOnInit ? function(cm, val, old) {if (old != Init) handle(cm, val, old);} : handle;
 }
 // Passed to option handlers when there is no old value.
 var Init = CodeMirror.Init = {toString: function(){return "CodeMirror.Init";}};
 // These two are, on init, called from the constructor because they
 // have to be initialized before the editor can start at all.
 option("value", "", function(cm, val) {
   cm.setValue(val);
 }, true);
 option("mode", null, function(cm, val) {
   cm.doc.modeOption = val;
   loadMode(cm);
 }, true);
 option("indentUnit", 2, loadMode, true);
 option("indentWithTabs", false);
 option("smartIndent", true);
 option("tabSize", 4, function(cm) {
   resetModeState(cm);
   clearCaches(cm);
   regChange(cm);
 }, true);
 option("lineSeparator", null, function(cm, val) {
   cm.doc.lineSep = val;
   if (!val) return;
   var newBreaks = [], lineNo = cm.doc.first;
   cm.doc.iter(function(line) {
     for (var pos = 0;;) {
       var found = line.text.indexOf(val, pos);
       if (found == -1) break;
       pos = found + val.length;
       newBreaks.push(Pos(lineNo, found));
     }
     lineNo++;
   });
   for (var i = newBreaks.length - 1; i >= 0; i--)
     replaceRange(cm.doc, val, newBreaks[i], Pos(newBreaks[i].line, newBreaks[i].ch + val.length))
 });
 option("specialChars", /[\t\u0000-\u0019\u00ad\u200b-\u200f\u2028\u2029\ufeff]/g, function(cm, val, old) {
   cm.state.specialChars = new RegExp(val.source + (val.test("\t") ? "" : "|\t"), "g");
   if (old != CodeMirror.Init) cm.refresh();
 });
 option("specialCharPlaceholder", defaultSpecialCharPlaceholder, function(cm) {cm.refresh();}, true);
 option("electricChars", true);
 option("inputStyle", mobile ? "contenteditable" : "textarea", function() {
   throw new Error("inputStyle can not (yet) be changed in a running editor"); // FIXME
 }, true);
 option("rtlMoveVisually", !windows);
 option("wholeLineUpdateBefore", true);
 option("theme", "default", function(cm) {
   themeChanged(cm);
   guttersChanged(cm);
 }, true);
 option("keyMap", "default", function(cm, val, old) {
   var next = getKeyMap(val);
   var prev = old != CodeMirror.Init && getKeyMap(old);
   if (prev && prev.detach) prev.detach(cm, next);
   if (next.attach) next.attach(cm, prev || null);
 });
 option("extraKeys", null);
 option("lineWrapping", false, wrappingChanged, true);
 option("gutters", [], function(cm) {
   setGuttersForLineNumbers(cm.options);
   guttersChanged(cm);
 }, true);
 option("fixedGutter", true, function(cm, val) {
   cm.display.gutters.style.left = val ? compensateForHScroll(cm.display) + "px" : "0";
   cm.refresh();
 }, true);
 option("coverGutterNextToScrollbar", false, function(cm) {updateScrollbars(cm);}, true);
 option("scrollbarStyle", "native", function(cm) {
   initScrollbars(cm);
   updateScrollbars(cm);
   cm.display.scrollbars.setScrollTop(cm.doc.scrollTop);
   cm.display.scrollbars.setScrollLeft(cm.doc.scrollLeft);
 }, true);
 option("lineNumbers", false, function(cm) {
   setGuttersForLineNumbers(cm.options);
   guttersChanged(cm);
 }, true);
 option("firstLineNumber", 1, guttersChanged, true);
 option("lineNumberFormatter", function(integer) {return integer;}, guttersChanged, true);
 option("showCursorWhenSelecting", false, updateSelection, true);
 option("resetSelectionOnContextMenu", true);
 option("lineWiseCopyCut", true);
 option("readOnly", false, function(cm, val) {
   if (val == "nocursor") {
     onBlur(cm);
     cm.display.input.blur();
     cm.display.disabled = true;
   } else {
     cm.display.disabled = false;
     if (!val) cm.display.input.reset();
   }
 });
 option("disableInput", false, function(cm, val) {if (!val) cm.display.input.reset();}, true);
 option("dragDrop", true, dragDropChanged);
 option("cursorBlinkRate", 530);
 option("cursorScrollMargin", 0);
 option("cursorHeight", 1, updateSelection, true);
 option("singleCursorHeightPerLine", true, updateSelection, true);
 option("workTime", 100);
 option("workDelay", 100);
 option("flattenSpans", true, resetModeState, true);
 option("addModeClass", false, resetModeState, true);
 option("pollInterval", 100);
 option("undoDepth", 200, function(cm, val){cm.doc.history.undoDepth = val;});
 option("historyEventDelay", 1250);
 option("viewportMargin", 10, function(cm){cm.refresh();}, true);
 option("maxHighlightLength", 10000, resetModeState, true);
 option("moveInputWithCursor", true, function(cm, val) {
   if (!val) cm.display.input.resetPosition();
 });
 option("tabindex", null, function(cm, val) {
   cm.display.input.getField().tabIndex = val || "";
 });
 option("autofocus", null);
 // MODE DEFINITION AND QUERYING
 // Known modes, by name and by MIME
 var modes = CodeMirror.modes = {}, mimeModes = CodeMirror.mimeModes = {};
 // Extra arguments are stored as the mode's dependencies, which is
 // used by (legacy) mechanisms like loadmode.js to automatically
 // load a mode. (Preferred mechanism is the require/define calls.)
 CodeMirror.defineMode = function(name, mode) {
   if (!CodeMirror.defaults.mode && name != "null") CodeMirror.defaults.mode = name;
   if (arguments.length > 2)
     mode.dependencies = Array.prototype.slice.call(arguments, 2);
   modes[name] = mode;
 };
 CodeMirror.defineMIME = function(mime, spec) {
   mimeModes[mime] = spec;
 };
 // Given a MIME type, a {name, ...options} config object, or a name
 // string, return a mode config object.
 CodeMirror.resolveMode = function(spec) {
   if (typeof spec == "string" && mimeModes.hasOwnProperty(spec)) {
     spec = mimeModes[spec];
   } else if (spec && typeof spec.name == "string" && mimeModes.hasOwnProperty(spec.name)) {
     var found = mimeModes[spec.name];
     if (typeof found == "string") found = {name: found};
     spec = createObj(found, spec);
     spec.name = found.name;
   } else if (typeof spec == "string" && /^[\w\-]+\/[\w\-]+\+xml$/.test(spec)) {
     return CodeMirror.resolveMode("application/xml");
   }
   if (typeof spec == "string") return {name: spec};
   else return spec || {name: "null"};
 };
 // Given a mode spec (anything that resolveMode accepts), find and
 // initialize an actual mode object.
 CodeMirror.getMode = function(options, spec) {
   var spec = CodeMirror.resolveMode(spec);
   var mfactory = modes[spec.name];
   if (!mfactory) return CodeMirror.getMode(options, "text/plain");
   var modeObj = mfactory(options, spec);
   if (modeExtensions.hasOwnProperty(spec.name)) {
     var exts = modeExtensions[spec.name];
     for (var prop in exts) {
       if (!exts.hasOwnProperty(prop)) continue;
       if (modeObj.hasOwnProperty(prop)) modeObj["_" + prop] = modeObj[prop];
       modeObj[prop] = exts[prop];
     }
   }
   modeObj.name = spec.name;
   if (spec.helperType) modeObj.helperType = spec.helperType;
   if (spec.modeProps) for (var prop in spec.modeProps)
     modeObj[prop] = spec.modeProps[prop];
   return modeObj;
 };
 // Minimal default mode.
 CodeMirror.defineMode("null", function() {
   return {token: function(stream) {stream.skipToEnd();}};
 });
 CodeMirror.defineMIME("text/plain", "null");
 // This can be used to attach properties to mode objects from
 // outside the actual mode definition.
 var modeExtensions = CodeMirror.modeExtensions = {};
 CodeMirror.extendMode = function(mode, properties) {
   var exts = modeExtensions.hasOwnProperty(mode) ? modeExtensions[mode] : (modeExtensions[mode] = {});
   copyObj(properties, exts);
 };
 // EXTENSIONS
 CodeMirror.defineExtension = function(name, func) {
   CodeMirror.prototype[name] = func;
 };
 CodeMirror.defineDocExtension = function(name, func) {
   Doc.prototype[name] = func;
 };
 CodeMirror.defineOption = option;
 var initHooks = [];
 CodeMirror.defineInitHook = function(f) {initHooks.push(f);};
 var helpers = CodeMirror.helpers = {};
 CodeMirror.registerHelper = function(type, name, value) {
   if (!helpers.hasOwnProperty(type)) helpers[type] = CodeMirror[type] = {_global: []};
   helpers[type][name] = value;
 };
 CodeMirror.registerGlobalHelper = function(type, name, predicate, value) {
   CodeMirror.registerHelper(type, name, value);
   helpers[type]._global.push({pred: predicate, val: value});
 };
 // MODE STATE HANDLING
 // Utility functions for working with state. Exported because nested
 // modes need to do this for their inner modes.
 var copyState = CodeMirror.copyState = function(mode, state) {
   if (state === true) return state;
   if (mode.copyState) return mode.copyState(state);
   var nstate = {};
   for (var n in state) {
     var val = state[n];
     if (val instanceof Array) val = val.concat([]);
     nstate[n] = val;
   }
   return nstate;
 };
 var startState = CodeMirror.startState = function(mode, a1, a2) {
   return mode.startState ? mode.startState(a1, a2) : true;
 };
 // Given a mode and a state (for that mode), find the inner mode and
 // state at the position that the state refers to.
 CodeMirror.innerMode = function(mode, state) {
   while (mode.innerMode) {
     var info = mode.innerMode(state);
     if (!info || info.mode == mode) break;
     state = info.state;
     mode = info.mode;
   }
   return info || {mode: mode, state: state};
 };
 // STANDARD COMMANDS
 // Commands are parameter-less actions that can be performed on an
 // editor, mostly used for keybindings.
 var commands = CodeMirror.commands = {
   selectAll: function(cm) {cm.setSelection(Pos(cm.firstLine(), 0), Pos(cm.lastLine()), sel_dontScroll);},
   singleSelection: function(cm) {
     cm.setSelection(cm.getCursor("anchor"), cm.getCursor("head"), sel_dontScroll);
   },
   killLine: function(cm) {
     deleteNearSelection(cm, function(range) {
       if (range.empty()) {
         var len = getLine(cm.doc, range.head.line).text.length;
         if (range.head.ch == len && range.head.line < cm.lastLine())
           return {from: range.head, to: Pos(range.head.line + 1, 0)};
         else
           return {from: range.head, to: Pos(range.head.line, len)};
       } else {
         return {from: range.from(), to: range.to()};
       }
     });
   },
   deleteLine: function(cm) {
     deleteNearSelection(cm, function(range) {
       return {from: Pos(range.from().line, 0),
               to: clipPos(cm.doc, Pos(range.to().line + 1, 0))};
     });
   },
   delLineLeft: function(cm) {
     deleteNearSelection(cm, function(range) {
       return {from: Pos(range.from().line, 0), to: range.from()};
     });
   },
   delWrappedLineLeft: function(cm) {
     deleteNearSelection(cm, function(range) {
       var top = cm.charCoords(range.head, "div").top + 5;
       var leftPos = cm.coordsChar({left: 0, top: top}, "div");
       return {from: leftPos, to: range.from()};
     });
   },
   delWrappedLineRight: function(cm) {
     deleteNearSelection(cm, function(range) {
       var top = cm.charCoords(range.head, "div").top + 5;
       var rightPos = cm.coordsChar({left: cm.display.lineDiv.offsetWidth + 100, top: top}, "div");
       return {from: range.from(), to: rightPos };
     });
   },
   undo: function(cm) {cm.undo();},
   redo: function(cm) {cm.redo();},
   undoSelection: function(cm) {cm.undoSelection();},
   redoSelection: function(cm) {cm.redoSelection();},
   goDocStart: function(cm) {cm.extendSelection(Pos(cm.firstLine(), 0));},
   goDocEnd: function(cm) {cm.extendSelection(Pos(cm.lastLine()));},
   goLineStart: function(cm) {
     cm.extendSelectionsBy(function(range) { return lineStart(cm, range.head.line); },
                           {origin: "+move", bias: 1});
   },
   goLineStartSmart: function(cm) {
     cm.extendSelectionsBy(function(range) {
       return lineStartSmart(cm, range.head);
     }, {origin: "+move", bias: 1});
   },
   goLineEnd: function(cm) {
     cm.extendSelectionsBy(function(range) { return lineEnd(cm, range.head.line); },
                           {origin: "+move", bias: -1});
   },
   goLineRight: function(cm) {
     cm.extendSelectionsBy(function(range) {
       var top = cm.charCoords(range.head, "div").top + 5;
       return cm.coordsChar({left: cm.display.lineDiv.offsetWidth + 100, top: top}, "div");
     }, sel_move);
   },
   goLineLeft: function(cm) {
     cm.extendSelectionsBy(function(range) {
       var top = cm.charCoords(range.head, "div").top + 5;
       return cm.coordsChar({left: 0, top: top}, "div");
     }, sel_move);
   },
   goLineLeftSmart: function(cm) {
     cm.extendSelectionsBy(function(range) {
       var top = cm.charCoords(range.head, "div").top + 5;
       var pos = cm.coordsChar({left: 0, top: top}, "div");
       if (pos.ch < cm.getLine(pos.line).search(/\S/)) return lineStartSmart(cm, range.head);
       return pos;
     }, sel_move);
   },
   goLineUp: function(cm) {cm.moveV(-1, "line");},
   goLineDown: function(cm) {cm.moveV(1, "line");},
   goPageUp: function(cm) {cm.moveV(-1, "page");},
   goPageDown: function(cm) {cm.moveV(1, "page");},
   goCharLeft: function(cm) {cm.moveH(-1, "char");},
   goCharRight: function(cm) {cm.moveH(1, "char");},
   goColumnLeft: function(cm) {cm.moveH(-1, "column");},
   goColumnRight: function(cm) {cm.moveH(1, "column");},
   goWordLeft: function(cm) {cm.moveH(-1, "word");},
   goGroupRight: function(cm) {cm.moveH(1, "group");},
   goGroupLeft: function(cm) {cm.moveH(-1, "group");},
   goWordRight: function(cm) {cm.moveH(1, "word");},
   delCharBefore: function(cm) {cm.deleteH(-1, "char");},
   delCharAfter: function(cm) {cm.deleteH(1, "char");},
   delWordBefore: function(cm) {cm.deleteH(-1, "word");},
   delWordAfter: function(cm) {cm.deleteH(1, "word");},
   delGroupBefore: function(cm) {cm.deleteH(-1, "group");},
   delGroupAfter: function(cm) {cm.deleteH(1, "group");},
   indentAuto: function(cm) {cm.indentSelection("smart");},
   indentMore: function(cm) {cm.indentSelection("add");},
   indentLess: function(cm) {cm.indentSelection("subtract");},
   insertTab: function(cm) {cm.replaceSelection("\t");},
   insertSoftTab: function(cm) {
     var spaces = [], ranges = cm.listSelections(), tabSize = cm.options.tabSize;
     for (var i = 0; i < ranges.length; i++) {
       var pos = ranges[i].from();
       var col = countColumn(cm.getLine(pos.line), pos.ch, tabSize);
       spaces.push(new Array(tabSize - col % tabSize + 1).join(" "));
     }
     cm.replaceSelections(spaces);
   },
   defaultTab: function(cm) {
     if (cm.somethingSelected()) cm.indentSelection("add");
     else cm.execCommand("insertTab");
   },
   transposeChars: function(cm) {
     runInOp(cm, function() {
       var ranges = cm.listSelections(), newSel = [];
       for (var i = 0; i < ranges.length; i++) {
         var cur = ranges[i].head, line = getLine(cm.doc, cur.line).text;
         if (line) {
           if (cur.ch == line.length) cur = new Pos(cur.line, cur.ch - 1);
           if (cur.ch > 0) {
             cur = new Pos(cur.line, cur.ch + 1);
             cm.replaceRange(line.charAt(cur.ch - 1) + line.charAt(cur.ch - 2),
                             Pos(cur.line, cur.ch - 2), cur, "+transpose");
           } else if (cur.line > cm.doc.first) {
             var prev = getLine(cm.doc, cur.line - 1).text;
             if (prev)
               cm.replaceRange(line.charAt(0) + cm.doc.lineSeparator() +
                               prev.charAt(prev.length - 1),
                               Pos(cur.line - 1, prev.length - 1), Pos(cur.line, 1), "+transpose");
           }
         }
         newSel.push(new Range(cur, cur));
       }
       cm.setSelections(newSel);
     });
   },
   newlineAndIndent: function(cm) {
     runInOp(cm, function() {
       var len = cm.listSelections().length;
       for (var i = 0; i < len; i++) {
         var range = cm.listSelections()[i];
         cm.replaceRange(cm.doc.lineSeparator(), range.anchor, range.head, "+input");
         cm.indentLine(range.from().line + 1, null, true);
         ensureCursorVisible(cm);
       }
     });
   },
   toggleOverwrite: function(cm) {cm.toggleOverwrite();}
 };


 // STANDARD KEYMAPS
 var keyMap = CodeMirror.keyMap = {};
 keyMap.basic = {
   "Left": "goCharLeft", "Right": "goCharRight", "Up": "goLineUp", "Down": "goLineDown",
   "End": "goLineEnd", "Home": "goLineStartSmart", "PageUp": "goPageUp", "PageDown": "goPageDown",
   "Delete": "delCharAfter", "Backspace": "delCharBefore", "Shift-Backspace": "delCharBefore",
   "Tab": "defaultTab", "Shift-Tab": "indentAuto",
   "Enter": "newlineAndIndent", "Insert": "toggleOverwrite",
   "Esc": "singleSelection"
 };
 // Note that the save and find-related commands aren't defined by
 // default. User code or addons can define them. Unknown commands
 // are simply ignored.
 keyMap.pcDefault = {
   "Ctrl-A": "selectAll", "Ctrl-D": "deleteLine", "Ctrl-Z": "undo", "Shift-Ctrl-Z": "redo", "Ctrl-Y": "redo",
   "Ctrl-Home": "goDocStart", "Ctrl-End": "goDocEnd", "Ctrl-Up": "goLineUp", "Ctrl-Down": "goLineDown",
   "Ctrl-Left": "goGroupLeft", "Ctrl-Right": "goGroupRight", "Alt-Left": "goLineStart", "Alt-Right": "goLineEnd",
   "Ctrl-Backspace": "delGroupBefore", "Ctrl-Delete": "delGroupAfter", "Ctrl-S": "save", "Ctrl-F": "find",
   "Ctrl-G": "findNext", "Shift-Ctrl-G": "findPrev", "Shift-Ctrl-F": "replace", "Shift-Ctrl-R": "replaceAll",
   "Ctrl-[": "indentLess", "Ctrl-]": "indentMore",
   "Ctrl-U": "undoSelection", "Shift-Ctrl-U": "redoSelection", "Alt-U": "redoSelection",
   fallthrough: "basic"
 };
 // Very basic readline/emacs-style bindings, which are standard on Mac.
 keyMap.emacsy = {
   "Ctrl-F": "goCharRight", "Ctrl-B": "goCharLeft", "Ctrl-P": "goLineUp", "Ctrl-N": "goLineDown",
   "Alt-F": "goWordRight", "Alt-B": "goWordLeft", "Ctrl-A": "goLineStart", "Ctrl-E": "goLineEnd",
   "Ctrl-V": "goPageDown", "Shift-Ctrl-V": "goPageUp", "Ctrl-D": "delCharAfter", "Ctrl-H": "delCharBefore",
   "Alt-D": "delWordAfter", "Alt-Backspace": "delWordBefore", "Ctrl-K": "killLine", "Ctrl-T": "transposeChars"
 };
 keyMap.macDefault = {
   "Cmd-A": "selectAll", "Cmd-D": "deleteLine", "Cmd-Z": "undo", "Shift-Cmd-Z": "redo", "Cmd-Y": "redo",
   "Cmd-Home": "goDocStart", "Cmd-Up": "goDocStart", "Cmd-End": "goDocEnd", "Cmd-Down": "goDocEnd", "Alt-Left": "goGroupLeft",
   "Alt-Right": "goGroupRight", "Cmd-Left": "goLineLeft", "Cmd-Right": "goLineRight", "Alt-Backspace": "delGroupBefore",
   "Ctrl-Alt-Backspace": "delGroupAfter", "Alt-Delete": "delGroupAfter", "Cmd-S": "save", "Cmd-F": "find",
   "Cmd-G": "findNext", "Shift-Cmd-G": "findPrev", "Cmd-Alt-F": "replace", "Shift-Cmd-Alt-F": "replaceAll",
   "Cmd-[": "indentLess", "Cmd-]": "indentMore", "Cmd-Backspace": "delWrappedLineLeft", "Cmd-Delete": "delWrappedLineRight",
   "Cmd-U": "undoSelection", "Shift-Cmd-U": "redoSelection", "Ctrl-Up": "goDocStart", "Ctrl-Down": "goDocEnd",
   fallthrough: ["basic", "emacsy"]
 };
 keyMap["default"] = mac ? keyMap.macDefault : keyMap.pcDefault;
 // KEYMAP DISPATCH
 function normalizeKeyName(name) {
   var parts = name.split(/-(?!$)/), name = parts[parts.length - 1];
   var alt, ctrl, shift, cmd;
   for (var i = 0; i < parts.length - 1; i++) {
     var mod = parts[i];
     if (/^(cmd|meta|m)$/i.test(mod)) cmd = true;
     else if (/^a(lt)?$/i.test(mod)) alt = true;
     else if (/^(c|ctrl|control)$/i.test(mod)) ctrl = true;
     else if (/^s(hift)$/i.test(mod)) shift = true;
     else throw new Error("Unrecognized modifier name: " + mod);
   }
   if (alt) name = "Alt-" + name;
   if (ctrl) name = "Ctrl-" + name;
   if (cmd) name = "Cmd-" + name;
   if (shift) name = "Shift-" + name;
   return name;
 }
 // This is a kludge to keep keymaps mostly working as raw objects
 // (backwards compatibility) while at the same time support features
 // like normalization and multi-stroke key bindings. It compiles a
 // new normalized keymap, and then updates the old object to reflect
 // this.
 CodeMirror.normalizeKeyMap = function(keymap) {
   var copy = {};
   for (var keyname in keymap) if (keymap.hasOwnProperty(keyname)) {
     var value = keymap[keyname];
     if (/^(name|fallthrough|(de|at)tach)$/.test(keyname)) continue;
     if (value == "...") { delete keymap[keyname]; continue; }
     var keys = map(keyname.split(" "), normalizeKeyName);
     for (var i = 0; i < keys.length; i++) {
       var val, name;
       if (i == keys.length - 1) {
         name = keys.join(" ");
         val = value;
       } else {
         name = keys.slice(0, i + 1).join(" ");
         val = "...";
       }
       var prev = copy[name];
       if (!prev) copy[name] = val;
       else if (prev != val) throw new Error("Inconsistent bindings for " + name);
     }
     delete keymap[keyname];
   }
   for (var prop in copy) keymap[prop] = copy[prop];
   return keymap;
 };
 var lookupKey = CodeMirror.lookupKey = function(key, map, handle, context) {
   map = getKeyMap(map);
   var found = map.call ? map.call(key, context) : map[key];
   if (found === false) return "nothing";
   if (found === "...") return "multi";
   if (found != null && handle(found)) return "handled";
   if (map.fallthrough) {
     if (Object.prototype.toString.call(map.fallthrough) != "[object Array]")
       return lookupKey(key, map.fallthrough, handle, context);
     for (var i = 0; i < map.fallthrough.length; i++) {
       var result = lookupKey(key, map.fallthrough[i], handle, context);
       if (result) return result;
     }
   }
 };
 // Modifier key presses don't count as 'real' key presses for the
 // purpose of keymap fallthrough.
 var isModifierKey = CodeMirror.isModifierKey = function(value) {
   var name = typeof value == "string" ? value : keyNames[value.keyCode];
   return name == "Ctrl" || name == "Alt" || name == "Shift" || name == "Mod";
 };
 // Look up the name of a key as indicated by an event object.
 var keyName = CodeMirror.keyName = function(event, noShift) {
   if (presto && event.keyCode == 34 && event["char"]) return false;
   var base = keyNames[event.keyCode], name = base;
   if (name == null || event.altGraphKey) return false;
   if (event.altKey && base != "Alt") name = "Alt-" + name;
   if ((flipCtrlCmd ? event.metaKey : event.ctrlKey) && base != "Ctrl") name = "Ctrl-" + name;
   if ((flipCtrlCmd ? event.ctrlKey : event.metaKey) && base != "Cmd") name = "Cmd-" + name;
   if (!noShift && event.shiftKey && base != "Shift") name = "Shift-" + name;
   return name;
 };
 function getKeyMap(val) {
   return typeof val == "string" ? keyMap[val] : val;
 }
 // FROMTEXTAREA
 CodeMirror.fromTextArea = function(textarea, options) {
   options = options ? copyObj(options) : {};
   options.value = textarea.value;
   if (!options.tabindex && textarea.tabIndex)
     options.tabindex = textarea.tabIndex;
   if (!options.placeholder && textarea.placeholder)
     options.placeholder = textarea.placeholder;
   // Set autofocus to true if this textarea is focused, or if it has
   // autofocus and no other element is focused.
   if (options.autofocus == null) {
     var hasFocus = activeElt();
     options.autofocus = hasFocus == textarea ||
       textarea.getAttribute("autofocus") != null && hasFocus == document.body;
   }
   function save() {textarea.value = cm.getValue();}
   if (textarea.form) {
     on(textarea.form, "submit", save);
     // Deplorable hack to make the submit method do the right thing.
     if (!options.leaveSubmitMethodAlone) {
       var form = textarea.form, realSubmit = form.submit;
       try {
         var wrappedSubmit = form.submit = function() {
           save();
           form.submit = realSubmit;
           form.submit();
           form.submit = wrappedSubmit;
         };
       } catch(e) {}
     }
   }
   options.finishInit = function(cm) {
     cm.save = save;
     cm.getTextArea = function() { return textarea; };
     cm.toTextArea = function() {
       cm.toTextArea = isNaN; // Prevent this from being ran twice
       save();
       textarea.parentNode.removeChild(cm.getWrapperElement());
       textarea.style.display = "";
       if (textarea.form) {
         off(textarea.form, "submit", save);
         if (typeof textarea.form.submit == "function")
           textarea.form.submit = realSubmit;
       }
     };
   };
   textarea.style.display = "none";
   var cm = CodeMirror(function(node) {
     textarea.parentNode.insertBefore(node, textarea.nextSibling);
   }, options);
   return cm;
 };
 // STRING STREAM
 // Fed to the mode parsers, provides helper functions to make
 // parsers more succinct.
 var StringStream = CodeMirror.StringStream = function(string, tabSize) {
   this.pos = this.start = 0;
   this.string = string;
   this.tabSize = tabSize || 8;
   this.lastColumnPos = this.lastColumnValue = 0;
   this.lineStart = 0;
 };
 StringStream.prototype = {
   eol: function() {return this.pos >= this.string.length;},
   sol: function() {return this.pos == this.lineStart;},
   peek: function() {return this.string.charAt(this.pos) || undefined;},
   next: function() {
     if (this.pos < this.string.length)
       return this.string.charAt(this.pos++);
   },
   eat: function(match) {
     var ch = this.string.charAt(this.pos);
     if (typeof match == "string") var ok = ch == match;
     else var ok = ch && (match.test ? match.test(ch) : match(ch));
     if (ok) {++this.pos; return ch;}
   },
   eatWhile: function(match) {
     var start = this.pos;
     while (this.eat(match)){}
     return this.pos > start;
   },
   eatSpace: function() {
     var start = this.pos;
     while (/[\s\u00a0]/.test(this.string.charAt(this.pos))) ++this.pos;
     return this.pos > start;
   },
   skipToEnd: function() {this.pos = this.string.length;},
   skipTo: function(ch) {
     var found = this.string.indexOf(ch, this.pos);
     if (found > -1) {this.pos = found; return true;}
   },
   backUp: function(n) {this.pos -= n;},
   column: function() {
     if (this.lastColumnPos < this.start) {
       this.lastColumnValue = countColumn(this.string, this.start, this.tabSize, this.lastColumnPos, this.lastColumnValue);
       this.lastColumnPos = this.start;
     }
     return this.lastColumnValue - (this.lineStart ? countColumn(this.string, this.lineStart, this.tabSize) : 0);
   },
   indentation: function() {
     return countColumn(this.string, null, this.tabSize) -
       (this.lineStart ? countColumn(this.string, this.lineStart, this.tabSize) : 0);
   },
   match: function(pattern, consume, caseInsensitive) {
     if (typeof pattern == "string") {
       var cased = function(str) {return caseInsensitive ? str.toLowerCase() : str;};
       var substr = this.string.substr(this.pos, pattern.length);
       if (cased(substr) == cased(pattern)) {
         if (consume !== false) this.pos += pattern.length;
         return true;
       }
     } else {
       var match = this.string.slice(this.pos).match(pattern);
       if (match && match.index > 0) return null;
       if (match && consume !== false) this.pos += match[0].length;
       return match;
     }
   },
   current: function(){return this.string.slice(this.start, this.pos);},
   hideFirstChars: function(n, inner) {
     this.lineStart += n;
     try { return inner(); }
     finally { this.lineStart -= n; }
   }
 };
 // TEXTMARKERS
 // Created with markText and setBookmark methods. A TextMarker is a
 // handle that can be used to clear or find a marked position in the
 // document. Line objects hold arrays (markedSpans) containing
 // {from, to, marker} object pointing to such marker objects, and
 // indicating that such a marker is present on that line. Multiple
 // lines may point to the same marker when it spans across lines.
 // The spans will have null for their from/to properties when the
 // marker continues beyond the start/end of the line. Markers have
 // links back to the lines they currently touch.
 var nextMarkerId = 0;
 var TextMarker = CodeMirror.TextMarker = function(doc, type) {
   this.lines = [];
   this.type = type;
   this.doc = doc;
   this.id = ++nextMarkerId;
 };
 eventMixin(TextMarker);
 // Clear the marker.
 TextMarker.prototype.clear = function() {
   if (this.explicitlyCleared) return;
   var cm = this.doc.cm, withOp = cm && !cm.curOp;
   if (withOp) startOperation(cm);
   if (hasHandler(this, "clear")) {
     var found = this.find();
     if (found) signalLater(this, "clear", found.from, found.to);
   }
   var min = null, max = null;
   for (var i = 0; i < this.lines.length; ++i) {
     var line = this.lines[i];
     var span = getMarkedSpanFor(line.markedSpans, this);
     if (cm && !this.collapsed) regLineChange(cm, lineNo(line), "text");
     else if (cm) {
       if (span.to != null) max = lineNo(line);
       if (span.from != null) min = lineNo(line);
     }
     line.markedSpans = removeMarkedSpan(line.markedSpans, span);
     if (span.from == null && this.collapsed && !lineIsHidden(this.doc, line) && cm)
       updateLineHeight(line, textHeight(cm.display));
   }
   if (cm && this.collapsed && !cm.options.lineWrapping) for (var i = 0; i < this.lines.length; ++i) {
     var visual = visualLine(this.lines[i]), len = lineLength(visual);
     if (len > cm.display.maxLineLength) {
       cm.display.maxLine = visual;
       cm.display.maxLineLength = len;
       cm.display.maxLineChanged = true;
     }
   }
   if (min != null && cm && this.collapsed) regChange(cm, min, max + 1);
   this.lines.length = 0;
   this.explicitlyCleared = true;
   if (this.atomic && this.doc.cantEdit) {
     this.doc.cantEdit = false;
     if (cm) reCheckSelection(cm.doc);
   }
   if (cm) signalLater(cm, "markerCleared", cm, this);
   if (withOp) endOperation(cm);
   if (this.parent) this.parent.clear();
 };
 // Find the position of the marker in the document. Returns a {from,
 // to} object by default. Side can be passed to get a specific side
 // -- 0 (both), -1 (left), or 1 (right). When lineObj is true, the
 // Pos objects returned contain a line object, rather than a line
 // number (used to prevent looking up the same line twice).
 TextMarker.prototype.find = function(side, lineObj) {
   if (side == null && this.type == "bookmark") side = 1;
   var from, to;
   for (var i = 0; i < this.lines.length; ++i) {
     var line = this.lines[i];
     var span = getMarkedSpanFor(line.markedSpans, this);
     if (span.from != null) {
       from = Pos(lineObj ? line : lineNo(line), span.from);
       if (side == -1) return from;
     }
     if (span.to != null) {
       to = Pos(lineObj ? line : lineNo(line), span.to);
       if (side == 1) return to;
     }
   }
   return from && {from: from, to: to};
 };
 // Signals that the marker's widget changed, and surrounding layout
 // should be recomputed.
 TextMarker.prototype.changed = function() {
   var pos = this.find(-1, true), widget = this, cm = this.doc.cm;
   if (!pos || !cm) return;
   runInOp(cm, function() {
     var line = pos.line, lineN = lineNo(pos.line);
     var view = findViewForLine(cm, lineN);
     if (view) {
       clearLineMeasurementCacheFor(view);
       cm.curOp.selectionChanged = cm.curOp.forceUpdate = true;
     }
     cm.curOp.updateMaxLine = true;
     if (!lineIsHidden(widget.doc, line) && widget.height != null) {
       var oldHeight = widget.height;
       widget.height = null;
       var dHeight = widgetHeight(widget) - oldHeight;
       if (dHeight)
         updateLineHeight(line, line.height + dHeight);
     }
   });
 };
 TextMarker.prototype.attachLine = function(line) {
   if (!this.lines.length && this.doc.cm) {
     var op = this.doc.cm.curOp;
     if (!op.maybeHiddenMarkers || indexOf(op.maybeHiddenMarkers, this) == -1)
       (op.maybeUnhiddenMarkers || (op.maybeUnhiddenMarkers = [])).push(this);
   }
   this.lines.push(line);
 };
 TextMarker.prototype.detachLine = function(line) {
   this.lines.splice(indexOf(this.lines, line), 1);
   if (!this.lines.length && this.doc.cm) {
     var op = this.doc.cm.curOp;
     (op.maybeHiddenMarkers || (op.maybeHiddenMarkers = [])).push(this);
   }
 };
 // Collapsed markers have unique ids, in order to be able to order
 // them, which is needed for uniquely determining an outer marker
 // when they overlap (they may nest, but not partially overlap).
 var nextMarkerId = 0;
 // Create a marker, wire it up to the right lines, and
 function markText(doc, from, to, options, type) {
   // Shared markers (across linked documents) are handled separately
   // (markTextShared will call out to this again, once per
   // document).
   if (options && options.shared) return markTextShared(doc, from, to, options, type);
   // Ensure we are in an operation.
   if (doc.cm && !doc.cm.curOp) return operation(doc.cm, markText)(doc, from, to, options, type);
   var marker = new TextMarker(doc, type), diff = cmp(from, to);
   if (options) copyObj(options, marker, false);
   // Don't connect empty markers unless clearWhenEmpty is false
   if (diff > 0 || diff == 0 && marker.clearWhenEmpty !== false)
     return marker;
   if (marker.replacedWith) {
     // Showing up as a widget implies collapsed (widget replaces text)
     marker.collapsed = true;
     marker.widgetNode = elt("span", [marker.replacedWith], "CodeMirror-widget");
     if (!options.handleMouseEvents) marker.widgetNode.setAttribute("cm-ignore-events", "true");
     if (options.insertLeft) marker.widgetNode.insertLeft = true;
   }
   if (marker.collapsed) {
     if (conflictingCollapsedRange(doc, from.line, from, to, marker) ||
         from.line != to.line && conflictingCollapsedRange(doc, to.line, from, to, marker))
       throw new Error("Inserting collapsed marker partially overlapping an existing one");
     sawCollapsedSpans = true;
   }
   if (marker.addToHistory)
     addChangeToHistory(doc, {from: from, to: to, origin: "markText"}, doc.sel, NaN);
   var curLine = from.line, cm = doc.cm, updateMaxLine;
   doc.iter(curLine, to.line + 1, function(line) {
     if (cm && marker.collapsed && !cm.options.lineWrapping && visualLine(line) == cm.display.maxLine)
       updateMaxLine = true;
     if (marker.collapsed && curLine != from.line) updateLineHeight(line, 0);
     addMarkedSpan(line, new MarkedSpan(marker,
                                        curLine == from.line ? from.ch : null,
                                        curLine == to.line ? to.ch : null));
     ++curLine;
   });
   // lineIsHidden depends on the presence of the spans, so needs a second pass
   if (marker.collapsed) doc.iter(from.line, to.line + 1, function(line) {
     if (lineIsHidden(doc, line)) updateLineHeight(line, 0);
   });
   if (marker.clearOnEnter) on(marker, "beforeCursorEnter", function() { marker.clear(); });
   if (marker.readOnly) {
     sawReadOnlySpans = true;
     if (doc.history.done.length || doc.history.undone.length)
       doc.clearHistory();
   }
   if (marker.collapsed) {
     marker.id = ++nextMarkerId;
     marker.atomic = true;
   }
   if (cm) {
     // Sync editor state
     if (updateMaxLine) cm.curOp.updateMaxLine = true;
     if (marker.collapsed)
       regChange(cm, from.line, to.line + 1);
     else if (marker.className || marker.title || marker.startStyle || marker.endStyle || marker.css)
       for (var i = from.line; i <= to.line; i++) regLineChange(cm, i, "text");
     if (marker.atomic) reCheckSelection(cm.doc);
     signalLater(cm, "markerAdded", cm, marker);
   }
   return marker;
 }
 // SHARED TEXTMARKERS
 // A shared marker spans multiple linked documents. It is
 // implemented as a meta-marker-object controlling multiple normal
 // markers.
 var SharedTextMarker = CodeMirror.SharedTextMarker = function(markers, primary) {
   this.markers = markers;
   this.primary = primary;
   for (var i = 0; i < markers.length; ++i)
     markers[i].parent = this;
 };
 eventMixin(SharedTextMarker);
 SharedTextMarker.prototype.clear = function() {
   if (this.explicitlyCleared) return;
   this.explicitlyCleared = true;
   for (var i = 0; i < this.markers.length; ++i)
     this.markers[i].clear();
   signalLater(this, "clear");
 };
 SharedTextMarker.prototype.find = function(side, lineObj) {
   return this.primary.find(side, lineObj);
 };
 function markTextShared(doc, from, to, options, type) {
   options = copyObj(options);
   options.shared = false;
   var markers = [markText(doc, from, to, options, type)], primary = markers[0];
   var widget = options.widgetNode;
   linkedDocs(doc, function(doc) {
     if (widget) options.widgetNode = widget.cloneNode(true);
     markers.push(markText(doc, clipPos(doc, from), clipPos(doc, to), options, type));
     for (var i = 0; i < doc.linked.length; ++i)
       if (doc.linked[i].isParent) return;
     primary = lst(markers);
   });
   return new SharedTextMarker(markers, primary);
 }
 function findSharedMarkers(doc) {
   return doc.findMarks(Pos(doc.first, 0), doc.clipPos(Pos(doc.lastLine())),
                        function(m) { return m.parent; });
 }
 function copySharedMarkers(doc, markers) {
   for (var i = 0; i < markers.length; i++) {
     var marker = markers[i], pos = marker.find();
     var mFrom = doc.clipPos(pos.from), mTo = doc.clipPos(pos.to);
     if (cmp(mFrom, mTo)) {
       var subMark = markText(doc, mFrom, mTo, marker.primary, marker.primary.type);
       marker.markers.push(subMark);
       subMark.parent = marker;
     }
   }
 }
 function detachSharedMarkers(markers) {
   for (var i = 0; i < markers.length; i++) {
     var marker = markers[i], linked = [marker.primary.doc];;
     linkedDocs(marker.primary.doc, function(d) { linked.push(d); });
     for (var j = 0; j < marker.markers.length; j++) {
       var subMarker = marker.markers[j];
       if (indexOf(linked, subMarker.doc) == -1) {
         subMarker.parent = null;
         marker.markers.splice(j--, 1);
       }
     }
   }
 }
 // TEXTMARKER SPANS
 function MarkedSpan(marker, from, to) {
   this.marker = marker;
   this.from = from; this.to = to;
 }
 // Search an array of spans for a span matching the given marker.
 function getMarkedSpanFor(spans, marker) {
   if (spans) for (var i = 0; i < spans.length; ++i) {
     var span = spans[i];
     if (span.marker == marker) return span;
   }
 }
 // Remove a span from an array, returning undefined if no spans are
 // left (we don't store arrays for lines without spans).
 function removeMarkedSpan(spans, span) {
   for (var r, i = 0; i < spans.length; ++i)
     if (spans[i] != span) (r || (r = [])).push(spans[i]);
   return r;
 }
 // Add a span to a line.
 function addMarkedSpan(line, span) {
   line.markedSpans = line.markedSpans ? line.markedSpans.concat([span]) : [span];
   span.marker.attachLine(line);
 }
 // Used for the algorithm that adjusts markers for a change in the
 // document. These functions cut an array of spans at a given
 // character position, returning an array of remaining chunks (or
 // undefined if nothing remains).
 function markedSpansBefore(old, startCh, isInsert) {
   if (old) for (var i = 0, nw; i < old.length; ++i) {
     var span = old[i], marker = span.marker;
     var startsBefore = span.from == null || (marker.inclusiveLeft ? span.from <= startCh : span.from < startCh);
     if (startsBefore || span.from == startCh && marker.type == "bookmark" && (!isInsert || !span.marker.insertLeft)) {
       var endsAfter = span.to == null || (marker.inclusiveRight ? span.to >= startCh : span.to > startCh);
       (nw || (nw = [])).push(new MarkedSpan(marker, span.from, endsAfter ? null : span.to));
     }
   }
   return nw;
 }
 function markedSpansAfter(old, endCh, isInsert) {
   if (old) for (var i = 0, nw; i < old.length; ++i) {
     var span = old[i], marker = span.marker;
     var endsAfter = span.to == null || (marker.inclusiveRight ? span.to >= endCh : span.to > endCh);
     if (endsAfter || span.from == endCh && marker.type == "bookmark" && (!isInsert || span.marker.insertLeft)) {
       var startsBefore = span.from == null || (marker.inclusiveLeft ? span.from <= endCh : span.from < endCh);
       (nw || (nw = [])).push(new MarkedSpan(marker, startsBefore ? null : span.from - endCh,
                                             span.to == null ? null : span.to - endCh));
     }
   }
   return nw;
 }
 // Given a change object, compute the new set of marker spans that
 // cover the line in which the change took place. Removes spans
 // entirely within the change, reconnects spans belonging to the
 // same marker that appear on both sides of the change, and cuts off
 // spans partially within the change. Returns an array of span
 // arrays with one element for each line in (after) the change.
 function stretchSpansOverChange(doc, change) {
   if (change.full) return null;
   var oldFirst = isLine(doc, change.from.line) && getLine(doc, change.from.line).markedSpans;
   var oldLast = isLine(doc, change.to.line) && getLine(doc, change.to.line).markedSpans;
   if (!oldFirst && !oldLast) return null;
   var startCh = change.from.ch, endCh = change.to.ch, isInsert = cmp(change.from, change.to) == 0;
   // Get the spans that 'stick out' on both sides
   var first = markedSpansBefore(oldFirst, startCh, isInsert);
   var last = markedSpansAfter(oldLast, endCh, isInsert);
   // Next, merge those two ends
   var sameLine = change.text.length == 1, offset = lst(change.text).length + (sameLine ? startCh : 0);
   if (first) {
     // Fix up .to properties of first
     for (var i = 0; i < first.length; ++i) {
       var span = first[i];
       if (span.to == null) {
         var found = getMarkedSpanFor(last, span.marker);
         if (!found) span.to = startCh;
         else if (sameLine) span.to = found.to == null ? null : found.to + offset;
       }
     }
   }
   if (last) {
     // Fix up .from in last (or move them into first in case of sameLine)
     for (var i = 0; i < last.length; ++i) {
       var span = last[i];
       if (span.to != null) span.to += offset;
       if (span.from == null) {
         var found = getMarkedSpanFor(first, span.marker);
         if (!found) {
           span.from = offset;
           if (sameLine) (first || (first = [])).push(span);
         }
       } else {
         span.from += offset;
         if (sameLine) (first || (first = [])).push(span);
       }
     }
   }
   // Make sure we didn't create any zero-length spans
   if (first) first = clearEmptySpans(first);
   if (last && last != first) last = clearEmptySpans(last);
   var newMarkers = [first];
   if (!sameLine) {
     // Fill gap with whole-line-spans
     var gap = change.text.length - 2, gapMarkers;
     if (gap > 0 && first)
       for (var i = 0; i < first.length; ++i)
         if (first[i].to == null)
           (gapMarkers || (gapMarkers = [])).push(new MarkedSpan(first[i].marker, null, null));
     for (var i = 0; i < gap; ++i)
       newMarkers.push(gapMarkers);
     newMarkers.push(last);
   }
   return newMarkers;
 }
 // Remove spans that are empty and don't have a clearWhenEmpty
 // option of false.
 function clearEmptySpans(spans) {
   for (var i = 0; i < spans.length; ++i) {
     var span = spans[i];
     if (span.from != null && span.from == span.to && span.marker.clearWhenEmpty !== false)
       spans.splice(i--, 1);
   }
   if (!spans.length) return null;
   return spans;
 }
 // Used for un/re-doing changes from the history. Combines the
 // result of computing the existing spans with the set of spans that
 // existed in the history (so that deleting around a span and then
 // undoing brings back the span).
 function mergeOldSpans(doc, change) {
   var old = getOldSpans(doc, change);
   var stretched = stretchSpansOverChange(doc, change);
   if (!old) return stretched;
   if (!stretched) return old;
   for (var i = 0; i < old.length; ++i) {
     var oldCur = old[i], stretchCur = stretched[i];
     if (oldCur && stretchCur) {
       spans: for (var j = 0; j < stretchCur.length; ++j) {
         var span = stretchCur[j];
         for (var k = 0; k < oldCur.length; ++k)
           if (oldCur[k].marker == span.marker) continue spans;
         oldCur.push(span);
       }
     } else if (stretchCur) {
       old[i] = stretchCur;
     }
   }
   return old;
 }
 // Used to 'clip' out readOnly ranges when making a change.
 function removeReadOnlyRanges(doc, from, to) {
   var markers = null;
   doc.iter(from.line, to.line + 1, function(line) {
     if (line.markedSpans) for (var i = 0; i < line.markedSpans.length; ++i) {
       var mark = line.markedSpans[i].marker;
       if (mark.readOnly && (!markers || indexOf(markers, mark) == -1))
         (markers || (markers = [])).push(mark);
     }
   });
   if (!markers) return null;
   var parts = [{from: from, to: to}];
   for (var i = 0; i < markers.length; ++i) {
     var mk = markers[i], m = mk.find(0);
     for (var j = 0; j < parts.length; ++j) {
       var p = parts[j];
       if (cmp(p.to, m.from) < 0 || cmp(p.from, m.to) > 0) continue;
       var newParts = [j, 1], dfrom = cmp(p.from, m.from), dto = cmp(p.to, m.to);
       if (dfrom < 0 || !mk.inclusiveLeft && !dfrom)
         newParts.push({from: p.from, to: m.from});
       if (dto > 0 || !mk.inclusiveRight && !dto)
         newParts.push({from: m.to, to: p.to});
       parts.splice.apply(parts, newParts);
       j += newParts.length - 1;
     }
   }
   return parts;
 }
 // Connect or disconnect spans from a line.
 function detachMarkedSpans(line) {
   var spans = line.markedSpans;
   if (!spans) return;
   for (var i = 0; i < spans.length; ++i)
     spans[i].marker.detachLine(line);
   line.markedSpans = null;
 }
 function attachMarkedSpans(line, spans) {
   if (!spans) return;
   for (var i = 0; i < spans.length; ++i)
     spans[i].marker.attachLine(line);
   line.markedSpans = spans;
 }
 // Helpers used when computing which overlapping collapsed span
 // counts as the larger one.
 function extraLeft(marker) { return marker.inclusiveLeft ? -1 : 0; }
 function extraRight(marker) { return marker.inclusiveRight ? 1 : 0; }
 // Returns a number indicating which of two overlapping collapsed
 // spans is larger (and thus includes the other). Falls back to
 // comparing ids when the spans cover exactly the same range.
 function compareCollapsedMarkers(a, b) {
   var lenDiff = a.lines.length - b.lines.length;
   if (lenDiff != 0) return lenDiff;
   var aPos = a.find(), bPos = b.find();
   var fromCmp = cmp(aPos.from, bPos.from) || extraLeft(a) - extraLeft(b);
   if (fromCmp) return -fromCmp;
   var toCmp = cmp(aPos.to, bPos.to) || extraRight(a) - extraRight(b);
   if (toCmp) return toCmp;
   return b.id - a.id;
 }
 // Find out whether a line ends or starts in a collapsed span. If
 // so, return the marker for that span.
 function collapsedSpanAtSide(line, start) {
   var sps = sawCollapsedSpans && line.markedSpans, found;
   if (sps) for (var sp, i = 0; i < sps.length; ++i) {
     sp = sps[i];
     if (sp.marker.collapsed && (start ? sp.from : sp.to) == null &&
         (!found || compareCollapsedMarkers(found, sp.marker) < 0))
       found = sp.marker;
   }
   return found;
 }
 function collapsedSpanAtStart(line) { return collapsedSpanAtSide(line, true); }
 function collapsedSpanAtEnd(line) { return collapsedSpanAtSide(line, false); }
 // Test whether there exists a collapsed span that partially
 // overlaps (covers the start or end, but not both) of a new span.
 // Such overlap is not allowed.
 function conflictingCollapsedRange(doc, lineNo, from, to, marker) {
   var line = getLine(doc, lineNo);
   var sps = sawCollapsedSpans && line.markedSpans;
   if (sps) for (var i = 0; i < sps.length; ++i) {
     var sp = sps[i];
     if (!sp.marker.collapsed) continue;
     var found = sp.marker.find(0);
     var fromCmp = cmp(found.from, from) || extraLeft(sp.marker) - extraLeft(marker);
     var toCmp = cmp(found.to, to) || extraRight(sp.marker) - extraRight(marker);
     if (fromCmp >= 0 && toCmp <= 0 || fromCmp <= 0 && toCmp >= 0) continue;
     if (fromCmp <= 0 && (cmp(found.to, from) > 0 || (sp.marker.inclusiveRight && marker.inclusiveLeft)) ||
         fromCmp >= 0 && (cmp(found.from, to) < 0 || (sp.marker.inclusiveLeft && marker.inclusiveRight)))
       return true;
   }
 }
 // A visual line is a line as drawn on the screen. Folding, for
 // example, can cause multiple logical lines to appear on the same
 // visual line. This finds the start of the visual line that the
 // given line is part of (usually that is the line itself).
 function visualLine(line) {
   var merged;
   while (merged = collapsedSpanAtStart(line))
     line = merged.find(-1, true).line;
   return line;
 }
 // Returns an array of logical lines that continue the visual line
 // started by the argument, or undefined if there are no such lines.
 function visualLineContinued(line) {
   var merged, lines;
   while (merged = collapsedSpanAtEnd(line)) {
     line = merged.find(1, true).line;
     (lines || (lines = [])).push(line);
   }
   return lines;
 }
 // Get the line number of the start of the visual line that the
 // given line number is part of.
 function visualLineNo(doc, lineN) {
   var line = getLine(doc, lineN), vis = visualLine(line);
   if (line == vis) return lineN;
   return lineNo(vis);
 }
 // Get the line number of the start of the next visual line after
 // the given line.
 function visualLineEndNo(doc, lineN) {
   if (lineN > doc.lastLine()) return lineN;
   var line = getLine(doc, lineN), merged;
   if (!lineIsHidden(doc, line)) return lineN;
   while (merged = collapsedSpanAtEnd(line))
     line = merged.find(1, true).line;
   return lineNo(line) + 1;
 }
 // Compute whether a line is hidden. Lines count as hidden when they
 // are part of a visual line that starts with another line, or when
 // they are entirely covered by collapsed, non-widget span.
 function lineIsHidden(doc, line) {
   var sps = sawCollapsedSpans && line.markedSpans;
   if (sps) for (var sp, i = 0; i < sps.length; ++i) {
     sp = sps[i];
     if (!sp.marker.collapsed) continue;
     if (sp.from == null) return true;
     if (sp.marker.widgetNode) continue;
     if (sp.from == 0 && sp.marker.inclusiveLeft && lineIsHiddenInner(doc, line, sp))
       return true;
   }
 }
 function lineIsHiddenInner(doc, line, span) {
   if (span.to == null) {
     var end = span.marker.find(1, true);
     return lineIsHiddenInner(doc, end.line, getMarkedSpanFor(end.line.markedSpans, span.marker));
   }
   if (span.marker.inclusiveRight && span.to == line.text.length)
     return true;
   for (var sp, i = 0; i < line.markedSpans.length; ++i) {
     sp = line.markedSpans[i];
     if (sp.marker.collapsed && !sp.marker.widgetNode && sp.from == span.to &&
         (sp.to == null || sp.to != span.from) &&
         (sp.marker.inclusiveLeft || span.marker.inclusiveRight) &&
         lineIsHiddenInner(doc, line, sp)) return true;
   }
 }
 // LINE WIDGETS
 // Line widgets are block elements displayed above or below a line.
 var LineWidget = CodeMirror.LineWidget = function(doc, node, options) {
   if (options) for (var opt in options) if (options.hasOwnProperty(opt))
     this[opt] = options[opt];
   this.doc = doc;
   this.node = node;
 };
 eventMixin(LineWidget);
 function adjustScrollWhenAboveVisible(cm, line, diff) {
   if (heightAtLine(line) < ((cm.curOp && cm.curOp.scrollTop) || cm.doc.scrollTop))
     addToScrollPos(cm, null, diff);
 }
 LineWidget.prototype.clear = function() {
   var cm = this.doc.cm, ws = this.line.widgets, line = this.line, no = lineNo(line);
   if (no == null || !ws) return;
   for (var i = 0; i < ws.length; ++i) if (ws[i] == this) ws.splice(i--, 1);
   if (!ws.length) line.widgets = null;
   var height = widgetHeight(this);
   updateLineHeight(line, Math.max(0, line.height - height));
   if (cm) runInOp(cm, function() {
     adjustScrollWhenAboveVisible(cm, line, -height);
     regLineChange(cm, no, "widget");
   });
 };
 LineWidget.prototype.changed = function() {
   var oldH = this.height, cm = this.doc.cm, line = this.line;
   this.height = null;
   var diff = widgetHeight(this) - oldH;
   if (!diff) return;
   updateLineHeight(line, line.height + diff);
   if (cm) runInOp(cm, function() {
     cm.curOp.forceUpdate = true;
     adjustScrollWhenAboveVisible(cm, line, diff);
   });
 };
 function widgetHeight(widget) {
   if (widget.height != null) return widget.height;
   var cm = widget.doc.cm;
   if (!cm) return 0;
   if (!contains(document.body, widget.node)) {
     var parentStyle = "position: relative;";
     if (widget.coverGutter)
       parentStyle += "margin-left: -" + cm.display.gutters.offsetWidth + "px;";
     if (widget.noHScroll)
       parentStyle += "width: " + cm.display.wrapper.clientWidth + "px;";
     removeChildrenAndAdd(cm.display.measure, elt("div", [widget.node], null, parentStyle));
   }
   return widget.height = widget.node.offsetHeight;
 }
 function addLineWidget(doc, handle, node, options) {
   var widget = new LineWidget(doc, node, options);
   var cm = doc.cm;
   if (cm && widget.noHScroll) cm.display.alignWidgets = true;
   changeLine(doc, handle, "widget", function(line) {
     var widgets = line.widgets || (line.widgets = []);
     if (widget.insertAt == null) widgets.push(widget);
     else widgets.splice(Math.min(widgets.length - 1, Math.max(0, widget.insertAt)), 0, widget);
     widget.line = line;
     if (cm && !lineIsHidden(doc, line)) {
       var aboveVisible = heightAtLine(line) < doc.scrollTop;
       updateLineHeight(line, line.height + widgetHeight(widget));
       if (aboveVisible) addToScrollPos(cm, null, widget.height);
       cm.curOp.forceUpdate = true;
     }
     return true;
   });
   return widget;
 }
 // LINE DATA STRUCTURE
 // Line objects. These hold state related to a line, including
 // highlighting info (the styles array).
 var Line = CodeMirror.Line = function(text, markedSpans, estimateHeight) {
   this.text = text;
   attachMarkedSpans(this, markedSpans);
   this.height = estimateHeight ? estimateHeight(this) : 1;
 };
 eventMixin(Line);
 Line.prototype.lineNo = function() { return lineNo(this); };
 // Change the content (text, markers) of a line. Automatically
 // invalidates cached information and tries to re-estimate the
 // line's height.
 function updateLine(line, text, markedSpans, estimateHeight) {
   line.text = text;
   if (line.stateAfter) line.stateAfter = null;
   if (line.styles) line.styles = null;
   if (line.order != null) line.order = null;
   detachMarkedSpans(line);
   attachMarkedSpans(line, markedSpans);
   var estHeight = estimateHeight ? estimateHeight(line) : 1;
   if (estHeight != line.height) updateLineHeight(line, estHeight);
 }
 // Detach a line from the document tree and its markers.
 function cleanUpLine(line) {
   line.parent = null;
   detachMarkedSpans(line);
 }
 function extractLineClasses(type, output) {
   if (type) for (;;) {
     var lineClass = type.match(/(?:^|\s+)line-(background-)?(\S+)/);
     if (!lineClass) break;
     type = type.slice(0, lineClass.index) + type.slice(lineClass.index + lineClass[0].length);
     var prop = lineClass[1] ? "bgClass" : "textClass";
     if (output[prop] == null)
       output[prop] = lineClass[2];
     else if (!(new RegExp("(?:^|\s)" + lineClass[2] + "(?:$|\s)")).test(output[prop]))
       output[prop] += " " + lineClass[2];
   }
   return type;
 }
 function callBlankLine(mode, state) {
   if (mode.blankLine) return mode.blankLine(state);
   if (!mode.innerMode) return;
   var inner = CodeMirror.innerMode(mode, state);
   if (inner.mode.blankLine) return inner.mode.blankLine(inner.state);
 }
 function readToken(mode, stream, state, inner) {
   for (var i = 0; i < 10; i++) {
     if (inner) inner[0] = CodeMirror.innerMode(mode, state).mode;
     var style = mode.token(stream, state);
     if (stream.pos > stream.start) return style;
   }
   throw new Error("Mode " + mode.name + " failed to advance stream.");
 }
 // Utility for getTokenAt and getLineTokens
 function takeToken(cm, pos, precise, asArray) {
   function getObj(copy) {
     return {start: stream.start, end: stream.pos,
             string: stream.current(),
             type: style || null,
             state: copy ? copyState(doc.mode, state) : state};
   }
   var doc = cm.doc, mode = doc.mode, style;
   pos = clipPos(doc, pos);
   var line = getLine(doc, pos.line), state = getStateBefore(cm, pos.line, precise);
   var stream = new StringStream(line.text, cm.options.tabSize), tokens;
   if (asArray) tokens = [];
   while ((asArray || stream.pos < pos.ch) && !stream.eol()) {
     stream.start = stream.pos;
     style = readToken(mode, stream, state);
     if (asArray) tokens.push(getObj(true));
   }
   return asArray ? tokens : getObj();
 }
 // Run the given mode's parser over a line, calling f for each token.
 function runMode(cm, text, mode, state, f, lineClasses, forceToEnd) {
   var flattenSpans = mode.flattenSpans;
   if (flattenSpans == null) flattenSpans = cm.options.flattenSpans;
   var curStart = 0, curStyle = null;
   var stream = new StringStream(text, cm.options.tabSize), style;
   var inner = cm.options.addModeClass && [null];
   if (text == "") extractLineClasses(callBlankLine(mode, state), lineClasses);
   while (!stream.eol()) {
     if (stream.pos > cm.options.maxHighlightLength) {
       flattenSpans = false;
       if (forceToEnd) processLine(cm, text, state, stream.pos);
       stream.pos = text.length;
       style = null;
     } else {
       style = extractLineClasses(readToken(mode, stream, state, inner), lineClasses);
     }
     if (inner) {
       var mName = inner[0].name;
       if (mName) style = "m-" + (style ? mName + " " + style : mName);
     }
     if (!flattenSpans || curStyle != style) {
       while (curStart < stream.start) {
         curStart = Math.min(stream.start, curStart + 50000);
         f(curStart, curStyle);
       }
       curStyle = style;
     }
     stream.start = stream.pos;
   }
   while (curStart < stream.pos) {
     // Webkit seems to refuse to render text nodes longer than 57444 characters
     var pos = Math.min(stream.pos, curStart + 50000);
     f(pos, curStyle);
     curStart = pos;
   }
 }
 // Compute a style array (an array starting with a mode generation
 // -- for invalidation -- followed by pairs of end positions and
 // style strings), which is used to highlight the tokens on the
 // line.
 function highlightLine(cm, line, state, forceToEnd) {
   // A styles array always starts with a number identifying the
   // mode/overlays that it is based on (for easy invalidation).
   var st = [cm.state.modeGen], lineClasses = {};
   // Compute the base array of styles
   runMode(cm, line.text, cm.doc.mode, state, function(end, style) {
     st.push(end, style);
   }, lineClasses, forceToEnd);
   // Run overlays, adjust style array.
   for (var o = 0; o < cm.state.overlays.length; ++o) {
     var overlay = cm.state.overlays[o], i = 1, at = 0;
     runMode(cm, line.text, overlay.mode, true, function(end, style) {
       var start = i;
       // Ensure there's a token end at the current position, and that i points at it
       while (at < end) {
         var i_end = st[i];
         if (i_end > end)
           st.splice(i, 1, end, st[i+1], i_end);
         i += 2;
         at = Math.min(end, i_end);
       }
       if (!style) return;
       if (overlay.opaque) {
         st.splice(start, i - start, end, "cm-overlay " + style);
         i = start + 2;
       } else {
         for (; start < i; start += 2) {
           var cur = st[start+1];
           st[start+1] = (cur ? cur + " " : "") + "cm-overlay " + style;
         }
       }
     }, lineClasses);
   }
   return {styles: st, classes: lineClasses.bgClass || lineClasses.textClass ? lineClasses : null};
 }
 function getLineStyles(cm, line, updateFrontier) {
   if (!line.styles || line.styles[0] != cm.state.modeGen) {
     var state = getStateBefore(cm, lineNo(line));
     var result = highlightLine(cm, line, line.text.length > cm.options.maxHighlightLength ? copyState(cm.doc.mode, state) : state);
     line.stateAfter = state;
     line.styles = result.styles;
     if (result.classes) line.styleClasses = result.classes;
     else if (line.styleClasses) line.styleClasses = null;
     if (updateFrontier === cm.doc.frontier) cm.doc.frontier++;
   }
   return line.styles;
 }
 // Lightweight form of highlight -- proceed over this line and
 // update state, but don't save a style array. Used for lines that
 // aren't currently visible.
 function processLine(cm, text, state, startAt) {
   var mode = cm.doc.mode;
   var stream = new StringStream(text, cm.options.tabSize);
   stream.start = stream.pos = startAt || 0;
   if (text == "") callBlankLine(mode, state);
   while (!stream.eol()) {
     readToken(mode, stream, state);
     stream.start = stream.pos;
   }
 }
 // Convert a style as returned by a mode (either null, or a string
 // containing one or more styles) to a CSS style. This is cached,
 // and also looks for line-wide styles.
 var styleToClassCache = {}, styleToClassCacheWithMode = {};
 function interpretTokenStyle(style, options) {
   if (!style || /^\s*$/.test(style)) return null;
   var cache = options.addModeClass ? styleToClassCacheWithMode : styleToClassCache;
   return cache[style] ||
     (cache[style] = style.replace(/\S+/g, "cm-$&"));
 }
 // Render the DOM representation of the text of a line. Also builds
 // up a 'line map', which points at the DOM nodes that represent
 // specific stretches of text, and is used by the measuring code.
 // The returned object contains the DOM node, this map, and
 // information about line-wide styles that were set by the mode.
 function buildLineContent(cm, lineView) {
   // The padding-right forces the element to have a 'border', which
   // is needed on Webkit to be able to get line-level bounding
   // rectangles for it (in measureChar).
   var content = elt("span", null, null, webkit ? "padding-right: .1px" : null);
   var builder = {pre: elt("pre", [content], "CodeMirror-line"), content: content,
                  col: 0, pos: 0, cm: cm,
                  splitSpaces: (ie || webkit) && cm.getOption("lineWrapping")};
   lineView.measure = {};
   // Iterate over the logical lines that make up this visual line.
   for (var i = 0; i <= (lineView.rest ? lineView.rest.length : 0); i++) {
     var line = i ? lineView.rest[i - 1] : lineView.line, order;
     builder.pos = 0;
     builder.addToken = buildToken;
     // Optionally wire in some hacks into the token-rendering
     // algorithm, to deal with browser quirks.
     if (hasBadBidiRects(cm.display.measure) && (order = getOrder(line)))
       builder.addToken = buildTokenBadBidi(builder.addToken, order);
     builder.map = [];
     var allowFrontierUpdate = lineView != cm.display.externalMeasured && lineNo(line);
     insertLineContent(line, builder, getLineStyles(cm, line, allowFrontierUpdate));
     if (line.styleClasses) {
       if (line.styleClasses.bgClass)
         builder.bgClass = joinClasses(line.styleClasses.bgClass, builder.bgClass || "");
       if (line.styleClasses.textClass)
         builder.textClass = joinClasses(line.styleClasses.textClass, builder.textClass || "");
     }
     // Ensure at least a single node is present, for measuring.
     if (builder.map.length == 0)
       builder.map.push(0, 0, builder.content.appendChild(zeroWidthElement(cm.display.measure)));
     // Store the map and a cache object for the current logical line
     if (i == 0) {
       lineView.measure.map = builder.map;
       lineView.measure.cache = {};
     } else {
       (lineView.measure.maps || (lineView.measure.maps = [])).push(builder.map);
       (lineView.measure.caches || (lineView.measure.caches = [])).push({});
     }
   }
   // See issue #2901
   if (webkit && /\bcm-tab\b/.test(builder.content.lastChild.className))
     builder.content.className = "cm-tab-wrap-hack";
   signal(cm, "renderLine", cm, lineView.line, builder.pre);
   if (builder.pre.className)
     builder.textClass = joinClasses(builder.pre.className, builder.textClass || "");
   return builder;
 }
 function defaultSpecialCharPlaceholder(ch) {
   var token = elt("span", "\u2022", "cm-invalidchar");
   token.title = "\\u" + ch.charCodeAt(0).toString(16);
   token.setAttribute("aria-label", token.title);
   return token;
 }
 // Build up the DOM representation for a single token, and add it to
 // the line map. Takes care to render special characters separately.
 function buildToken(builder, text, style, startStyle, endStyle, title, css) {
   if (!text) return;
   var displayText = builder.splitSpaces ? text.replace(/ {3,}/g, splitSpaces) : text;
   var special = builder.cm.state.specialChars, mustWrap = false;
   if (!special.test(text)) {
     builder.col += text.length;
     var content = document.createTextNode(displayText);
     builder.map.push(builder.pos, builder.pos + text.length, content);
     if (ie && ie_version < 9) mustWrap = true;
     builder.pos += text.length;
   } else {
     var content = document.createDocumentFragment(), pos = 0;
     while (true) {
       special.lastIndex = pos;
       var m = special.exec(text);
       var skipped = m ? m.index - pos : text.length - pos;
       if (skipped) {
         var txt = document.createTextNode(displayText.slice(pos, pos + skipped));
         if (ie && ie_version < 9) content.appendChild(elt("span", [txt]));
         else content.appendChild(txt);
         builder.map.push(builder.pos, builder.pos + skipped, txt);
         builder.col += skipped;
         builder.pos += skipped;
       }
       if (!m) break;
       pos += skipped + 1;
       if (m[0] == "\t") {
         var tabSize = builder.cm.options.tabSize, tabWidth = tabSize - builder.col % tabSize;
         var txt = content.appendChild(elt("span", spaceStr(tabWidth), "cm-tab"));
         txt.setAttribute("role", "presentation");
         txt.setAttribute("cm-text", "\t");
         builder.col += tabWidth;
       } else if (m[0] == "\r" || m[0] == "\n") {
         var txt = content.appendChild(elt("span", m[0] == "\r" ? "␍" : "␤", "cm-invalidchar"));
         txt.setAttribute("cm-text", m[0]);
         builder.col += 1;
       } else {
         var txt = builder.cm.options.specialCharPlaceholder(m[0]);
         txt.setAttribute("cm-text", m[0]);
         if (ie && ie_version < 9) content.appendChild(elt("span", [txt]));
         else content.appendChild(txt);
         builder.col += 1;
       }
       builder.map.push(builder.pos, builder.pos + 1, txt);
       builder.pos++;
     }
   }
   if (style || startStyle || endStyle || mustWrap || css) {
     var fullStyle = style || "";
     if (startStyle) fullStyle += startStyle;
     if (endStyle) fullStyle += endStyle;
     var token = elt("span", [content], fullStyle, css);
     if (title) token.title = title;
     return builder.content.appendChild(token);
   }
   builder.content.appendChild(content);
 }
 function splitSpaces(old) {
   var out = " ";
   for (var i = 0; i < old.length - 2; ++i) out += i % 2 ? " " : "\u00a0";
   out += " ";
   return out;
 }
 // Work around nonsense dimensions being reported for stretches of
 // right-to-left text.
 function buildTokenBadBidi(inner, order) {
   return function(builder, text, style, startStyle, endStyle, title, css) {
     style = style ? style + " cm-force-border" : "cm-force-border";
     var start = builder.pos, end = start + text.length;
     for (;;) {
       // Find the part that overlaps with the start of this text
       for (var i = 0; i < order.length; i++) {
         var part = order[i];
         if (part.to > start && part.from <= start) break;
       }
       if (part.to >= end) return inner(builder, text, style, startStyle, endStyle, title, css);
       inner(builder, text.slice(0, part.to - start), style, startStyle, null, title, css);
       startStyle = null;
       text = text.slice(part.to - start);
       start = part.to;
     }
   };
 }
 function buildCollapsedSpan(builder, size, marker, ignoreWidget) {
   var widget = !ignoreWidget && marker.widgetNode;
   if (widget) builder.map.push(builder.pos, builder.pos + size, widget);
   if (!ignoreWidget && builder.cm.display.input.needsContentAttribute) {
     if (!widget)
       widget = builder.content.appendChild(document.createElement("span"));
     widget.setAttribute("cm-marker", marker.id);
   }
   if (widget) {
     builder.cm.display.input.setUneditable(widget);
     builder.content.appendChild(widget);
   }
   builder.pos += size;
 }
 // Outputs a number of spans to make up a line, taking highlighting
 // and marked text into account.
 function insertLineContent(line, builder, styles) {
   var spans = line.markedSpans, allText = line.text, at = 0;
   if (!spans) {
     for (var i = 1; i < styles.length; i+=2)
       builder.addToken(builder, allText.slice(at, at = styles[i]), interpretTokenStyle(styles[i+1], builder.cm.options));
     return;
   }
   var len = allText.length, pos = 0, i = 1, text = "", style, css;
   var nextChange = 0, spanStyle, spanEndStyle, spanStartStyle, title, collapsed;
   for (;;) {
     if (nextChange == pos) { // Update current marker set
       spanStyle = spanEndStyle = spanStartStyle = title = css = "";
       collapsed = null; nextChange = Infinity;
       var foundBookmarks = [];
       for (var j = 0; j < spans.length; ++j) {
         var sp = spans[j], m = sp.marker;
         if (m.type == "bookmark" && sp.from == pos && m.widgetNode) {
           foundBookmarks.push(m);
         } else if (sp.from <= pos && (sp.to == null || sp.to > pos || m.collapsed && sp.to == pos && sp.from == pos)) {
           if (sp.to != null && sp.to != pos && nextChange > sp.to) {
             nextChange = sp.to;
             spanEndStyle = "";
           }
           if (m.className) spanStyle += " " + m.className;
           if (m.css) css = m.css;
           if (m.startStyle && sp.from == pos) spanStartStyle += " " + m.startStyle;
           if (m.endStyle && sp.to == nextChange) spanEndStyle += " " + m.endStyle;
           if (m.title && !title) title = m.title;
           if (m.collapsed && (!collapsed || compareCollapsedMarkers(collapsed.marker, m) < 0))
             collapsed = sp;
         } else if (sp.from > pos && nextChange > sp.from) {
           nextChange = sp.from;
         }
       }
       if (collapsed && (collapsed.from || 0) == pos) {
         buildCollapsedSpan(builder, (collapsed.to == null ? len + 1 : collapsed.to) - pos,
                            collapsed.marker, collapsed.from == null);
         if (collapsed.to == null) return;
         if (collapsed.to == pos) collapsed = false;
       }
       if (!collapsed && foundBookmarks.length) for (var j = 0; j < foundBookmarks.length; ++j)
         buildCollapsedSpan(builder, 0, foundBookmarks[j]);
     }
     if (pos >= len) break;
     var upto = Math.min(len, nextChange);
     while (true) {
       if (text) {
         var end = pos + text.length;
         if (!collapsed) {
           var tokenText = end > upto ? text.slice(0, upto - pos) : text;
           builder.addToken(builder, tokenText, style ? style + spanStyle : spanStyle,
                            spanStartStyle, pos + tokenText.length == nextChange ? spanEndStyle : "", title, css);
         }
         if (end >= upto) {text = text.slice(upto - pos); pos = upto; break;}
         pos = end;
         spanStartStyle = "";
       }
       text = allText.slice(at, at = styles[i++]);
       style = interpretTokenStyle(styles[i++], builder.cm.options);
     }
   }
 }
 // DOCUMENT DATA STRUCTURE
 // By default, updates that start and end at the beginning of a line
 // are treated specially, in order to make the association of line
 // widgets and marker elements with the text behave more intuitive.
 function isWholeLineUpdate(doc, change) {
   return change.from.ch == 0 && change.to.ch == 0 && lst(change.text) == "" &&
     (!doc.cm || doc.cm.options.wholeLineUpdateBefore);
 }
 // Perform a change on the document data structure.
 function updateDoc(doc, change, markedSpans, estimateHeight) {
   function spansFor(n) {return markedSpans ? markedSpans[n] : null;}
   function update(line, text, spans) {
     updateLine(line, text, spans, estimateHeight);
     signalLater(line, "change", line, change);
   }
   function linesFor(start, end) {
     for (var i = start, result = []; i < end; ++i)
       result.push(new Line(text[i], spansFor(i), estimateHeight));
     return result;
   }
   var from = change.from, to = change.to, text = change.text;
   var firstLine = getLine(doc, from.line), lastLine = getLine(doc, to.line);
   var lastText = lst(text), lastSpans = spansFor(text.length - 1), nlines = to.line - from.line;
   // Adjust the line structure
   if (change.full) {
     doc.insert(0, linesFor(0, text.length));
     doc.remove(text.length, doc.size - text.length);
   } else if (isWholeLineUpdate(doc, change)) {
     // This is a whole-line replace. Treated specially to make
     // sure line objects move the way they are supposed to.
     var added = linesFor(0, text.length - 1);
     update(lastLine, lastLine.text, lastSpans);
     if (nlines) doc.remove(from.line, nlines);
     if (added.length) doc.insert(from.line, added);
   } else if (firstLine == lastLine) {
     if (text.length == 1) {
       update(firstLine, firstLine.text.slice(0, from.ch) + lastText + firstLine.text.slice(to.ch), lastSpans);
     } else {
       var added = linesFor(1, text.length - 1);
       added.push(new Line(lastText + firstLine.text.slice(to.ch), lastSpans, estimateHeight));
       update(firstLine, firstLine.text.slice(0, from.ch) + text[0], spansFor(0));
       doc.insert(from.line + 1, added);
     }
   } else if (text.length == 1) {
     update(firstLine, firstLine.text.slice(0, from.ch) + text[0] + lastLine.text.slice(to.ch), spansFor(0));
     doc.remove(from.line + 1, nlines);
   } else {
     update(firstLine, firstLine.text.slice(0, from.ch) + text[0], spansFor(0));
     update(lastLine, lastText + lastLine.text.slice(to.ch), lastSpans);
     var added = linesFor(1, text.length - 1);
     if (nlines > 1) doc.remove(from.line + 1, nlines - 1);
     doc.insert(from.line + 1, added);
   }
   signalLater(doc, "change", doc, change);
 }
 // The document is represented as a BTree consisting of leaves, with
 // chunk of lines in them, and branches, with up to ten leaves or
 // other branch nodes below them. The top node is always a branch
 // node, and is the document object itself (meaning it has
 // additional methods and properties).
 //
 // All nodes have parent links. The tree is used both to go from
 // line numbers to line objects, and to go from objects to numbers.
 // It also indexes by height, and is used to convert between height
 // and line object, and to find the total height of the document.
 //
 // See also http://marijnhaverbeke.nl/blog/codemirror-line-tree.html
 function LeafChunk(lines) {
   this.lines = lines;
   this.parent = null;
   for (var i = 0, height = 0; i < lines.length; ++i) {
     lines[i].parent = this;
     height += lines[i].height;
   }
   this.height = height;
 }
 LeafChunk.prototype = {
   chunkSize: function() { return this.lines.length; },
   // Remove the n lines at offset 'at'.
   removeInner: function(at, n) {
     for (var i = at, e = at + n; i < e; ++i) {
       var line = this.lines[i];
       this.height -= line.height;
       cleanUpLine(line);
       signalLater(line, "delete");
     }
     this.lines.splice(at, n);
   },
   // Helper used to collapse a small branch into a single leaf.
   collapse: function(lines) {
     lines.push.apply(lines, this.lines);
   },
   // Insert the given array of lines at offset 'at', count them as
   // having the given height.
   insertInner: function(at, lines, height) {
     this.height += height;
     this.lines = this.lines.slice(0, at).concat(lines).concat(this.lines.slice(at));
     for (var i = 0; i < lines.length; ++i) lines[i].parent = this;
   },
   // Used to iterate over a part of the tree.
   iterN: function(at, n, op) {
     for (var e = at + n; at < e; ++at)
       if (op(this.lines[at])) return true;
   }
 };
 function BranchChunk(children) {
   this.children = children;
   var size = 0, height = 0;
   for (var i = 0; i < children.length; ++i) {
     var ch = children[i];
     size += ch.chunkSize(); height += ch.height;
     ch.parent = this;
   }
   this.size = size;
   this.height = height;
   this.parent = null;
 }
 BranchChunk.prototype = {
   chunkSize: function() { return this.size; },
   removeInner: function(at, n) {
     this.size -= n;
     for (var i = 0; i < this.children.length; ++i) {
       var child = this.children[i], sz = child.chunkSize();
       if (at < sz) {
         var rm = Math.min(n, sz - at), oldHeight = child.height;
         child.removeInner(at, rm);
         this.height -= oldHeight - child.height;
         if (sz == rm) { this.children.splice(i--, 1); child.parent = null; }
         if ((n -= rm) == 0) break;
         at = 0;
       } else at -= sz;
     }
     // If the result is smaller than 25 lines, ensure that it is a
     // single leaf node.
     if (this.size - n < 25 &&
         (this.children.length > 1 || !(this.children[0] instanceof LeafChunk))) {
       var lines = [];
       this.collapse(lines);
       this.children = [new LeafChunk(lines)];
       this.children[0].parent = this;
     }
   },
   collapse: function(lines) {
     for (var i = 0; i < this.children.length; ++i) this.children[i].collapse(lines);
   },
   insertInner: function(at, lines, height) {
     this.size += lines.length;
     this.height += height;
     for (var i = 0; i < this.children.length; ++i) {
       var child = this.children[i], sz = child.chunkSize();
       if (at <= sz) {
         child.insertInner(at, lines, height);
         if (child.lines && child.lines.length > 50) {
           while (child.lines.length > 50) {
             var spilled = child.lines.splice(child.lines.length - 25, 25);
             var newleaf = new LeafChunk(spilled);
             child.height -= newleaf.height;
             this.children.splice(i + 1, 0, newleaf);
             newleaf.parent = this;
           }
           this.maybeSpill();
         }
         break;
       }
       at -= sz;
     }
   },
   // When a node has grown, check whether it should be split.
   maybeSpill: function() {
     if (this.children.length <= 10) return;
     var me = this;
     do {
       var spilled = me.children.splice(me.children.length - 5, 5);
       var sibling = new BranchChunk(spilled);
       if (!me.parent) { // Become the parent node
         var copy = new BranchChunk(me.children);
         copy.parent = me;
         me.children = [copy, sibling];
         me = copy;
       } else {
         me.size -= sibling.size;
         me.height -= sibling.height;
         var myIndex = indexOf(me.parent.children, me);
         me.parent.children.splice(myIndex + 1, 0, sibling);
       }
       sibling.parent = me.parent;
     } while (me.children.length > 10);
     me.parent.maybeSpill();
   },
   iterN: function(at, n, op) {
     for (var i = 0; i < this.children.length; ++i) {
       var child = this.children[i], sz = child.chunkSize();
       if (at < sz) {
         var used = Math.min(n, sz - at);
         if (child.iterN(at, used, op)) return true;
         if ((n -= used) == 0) break;
         at = 0;
       } else at -= sz;
     }
   }
 };
 var nextDocId = 0;
 var Doc = CodeMirror.Doc = function(text, mode, firstLine, lineSep) {
   if (!(this instanceof Doc)) return new Doc(text, mode, firstLine, lineSep);
   if (firstLine == null) firstLine = 0;
   BranchChunk.call(this, [new LeafChunk([new Line("", null)])]);
   this.first = firstLine;
   this.scrollTop = this.scrollLeft = 0;
   this.cantEdit = false;
   this.cleanGeneration = 1;
   this.frontier = firstLine;
   var start = Pos(firstLine, 0);
   this.sel = simpleSelection(start);
   this.history = new History(null);
   this.id = ++nextDocId;
   this.modeOption = mode;
   this.lineSep = lineSep;
   if (typeof text == "string") text = this.splitLines(text);
   updateDoc(this, {from: start, to: start, text: text});
   setSelection(this, simpleSelection(start), sel_dontScroll);
 };
 Doc.prototype = createObj(BranchChunk.prototype, {
   constructor: Doc,
   // Iterate over the document. Supports two forms -- with only one
   // argument, it calls that for each line in the document. With
   // three, it iterates over the range given by the first two (with
   // the second being non-inclusive).
   iter: function(from, to, op) {
     if (op) this.iterN(from - this.first, to - from, op);
     else this.iterN(this.first, this.first + this.size, from);
   },
   // Non-public interface for adding and removing lines.
   insert: function(at, lines) {
     var height = 0;
     for (var i = 0; i < lines.length; ++i) height += lines[i].height;
     this.insertInner(at - this.first, lines, height);
   },
   remove: function(at, n) { this.removeInner(at - this.first, n); },
   // From here, the methods are part of the public interface. Most
   // are also available from CodeMirror (editor) instances.
   getValue: function(lineSep) {
     var lines = getLines(this, this.first, this.first + this.size);
     if (lineSep === false) return lines;
     return lines.join(lineSep || this.lineSeparator());
   },
   setValue: docMethodOp(function(code) {
     var top = Pos(this.first, 0), last = this.first + this.size - 1;
     makeChange(this, {from: top, to: Pos(last, getLine(this, last).text.length),
                       text: this.splitLines(code), origin: "setValue", full: true}, true);
     setSelection(this, simpleSelection(top));
   }),
   replaceRange: function(code, from, to, origin) {
     from = clipPos(this, from);
     to = to ? clipPos(this, to) : from;
     replaceRange(this, code, from, to, origin);
   },
   getRange: function(from, to, lineSep) {
     var lines = getBetween(this, clipPos(this, from), clipPos(this, to));
     if (lineSep === false) return lines;
     return lines.join(lineSep || this.lineSeparator());
   },
   getLine: function(line) {var l = this.getLineHandle(line); return l && l.text;},
   getLineHandle: function(line) {if (isLine(this, line)) return getLine(this, line);},
   getLineNumber: function(line) {return lineNo(line);},
   getLineHandleVisualStart: function(line) {
     if (typeof line == "number") line = getLine(this, line);
     return visualLine(line);
   },
   lineCount: function() {return this.size;},
   firstLine: function() {return this.first;},
   lastLine: function() {return this.first + this.size - 1;},
   clipPos: function(pos) {return clipPos(this, pos);},
   getCursor: function(start) {
     var range = this.sel.primary(), pos;
     if (start == null || start == "head") pos = range.head;
     else if (start == "anchor") pos = range.anchor;
     else if (start == "end" || start == "to" || start === false) pos = range.to();
     else pos = range.from();
     return pos;
   },
   listSelections: function() { return this.sel.ranges; },
   somethingSelected: function() {return this.sel.somethingSelected();},
   setCursor: docMethodOp(function(line, ch, options) {
     setSimpleSelection(this, clipPos(this, typeof line == "number" ? Pos(line, ch || 0) : line), null, options);
   }),
   setSelection: docMethodOp(function(anchor, head, options) {
     setSimpleSelection(this, clipPos(this, anchor), clipPos(this, head || anchor), options);
   }),
   extendSelection: docMethodOp(function(head, other, options) {
     extendSelection(this, clipPos(this, head), other && clipPos(this, other), options);
   }),
   extendSelections: docMethodOp(function(heads, options) {
     extendSelections(this, clipPosArray(this, heads, options));
   }),
   extendSelectionsBy: docMethodOp(function(f, options) {
     extendSelections(this, map(this.sel.ranges, f), options);
   }),
   setSelections: docMethodOp(function(ranges, primary, options) {
     if (!ranges.length) return;
     for (var i = 0, out = []; i < ranges.length; i++)
       out[i] = new Range(clipPos(this, ranges[i].anchor),
                          clipPos(this, ranges[i].head));
     if (primary == null) primary = Math.min(ranges.length - 1, this.sel.primIndex);
     setSelection(this, normalizeSelection(out, primary), options);
   }),
   addSelection: docMethodOp(function(anchor, head, options) {
     var ranges = this.sel.ranges.slice(0);
     ranges.push(new Range(clipPos(this, anchor), clipPos(this, head || anchor)));
     setSelection(this, normalizeSelection(ranges, ranges.length - 1), options);
   }),
   getSelection: function(lineSep) {
     var ranges = this.sel.ranges, lines;
     for (var i = 0; i < ranges.length; i++) {
       var sel = getBetween(this, ranges[i].from(), ranges[i].to());
       lines = lines ? lines.concat(sel) : sel;
     }
     if (lineSep === false) return lines;
     else return lines.join(lineSep || this.lineSeparator());
   },
   getSelections: function(lineSep) {
     var parts = [], ranges = this.sel.ranges;
     for (var i = 0; i < ranges.length; i++) {
       var sel = getBetween(this, ranges[i].from(), ranges[i].to());
       if (lineSep !== false) sel = sel.join(lineSep || this.lineSeparator());
       parts[i] = sel;
     }
     return parts;
   },
   replaceSelection: function(code, collapse, origin) {
     var dup = [];
     for (var i = 0; i < this.sel.ranges.length; i++)
       dup[i] = code;
     this.replaceSelections(dup, collapse, origin || "+input");
   },
   replaceSelections: docMethodOp(function(code, collapse, origin) {
     var changes = [], sel = this.sel;
     for (var i = 0; i < sel.ranges.length; i++) {
       var range = sel.ranges[i];
       changes[i] = {from: range.from(), to: range.to(), text: this.splitLines(code[i]), origin: origin};
     }
     var newSel = collapse && collapse != "end" && computeReplacedSel(this, changes, collapse);
     for (var i = changes.length - 1; i >= 0; i--)
       makeChange(this, changes[i]);
     if (newSel) setSelectionReplaceHistory(this, newSel);
     else if (this.cm) ensureCursorVisible(this.cm);
   }),
   undo: docMethodOp(function() {makeChangeFromHistory(this, "undo");}),
   redo: docMethodOp(function() {makeChangeFromHistory(this, "redo");}),
   undoSelection: docMethodOp(function() {makeChangeFromHistory(this, "undo", true);}),
   redoSelection: docMethodOp(function() {makeChangeFromHistory(this, "redo", true);}),
   setExtending: function(val) {this.extend = val;},
   getExtending: function() {return this.extend;},
   historySize: function() {
     var hist = this.history, done = 0, undone = 0;
     for (var i = 0; i < hist.done.length; i++) if (!hist.done[i].ranges) ++done;
     for (var i = 0; i < hist.undone.length; i++) if (!hist.undone[i].ranges) ++undone;
     return {undo: done, redo: undone};
   },
   clearHistory: function() {this.history = new History(this.history.maxGeneration);},
   markClean: function() {
     this.cleanGeneration = this.changeGeneration(true);
   },
   changeGeneration: function(forceSplit) {
     if (forceSplit)
       this.history.lastOp = this.history.lastSelOp = this.history.lastOrigin = null;
     return this.history.generation;
   },
   isClean: function (gen) {
     return this.history.generation == (gen || this.cleanGeneration);
   },
   getHistory: function() {
     return {done: copyHistoryArray(this.history.done),
             undone: copyHistoryArray(this.history.undone)};
   },
   setHistory: function(histData) {
     var hist = this.history = new History(this.history.maxGeneration);
     hist.done = copyHistoryArray(histData.done.slice(0), null, true);
     hist.undone = copyHistoryArray(histData.undone.slice(0), null, true);
   },
   addLineClass: docMethodOp(function(handle, where, cls) {
     return changeLine(this, handle, where == "gutter" ? "gutter" : "class", function(line) {
       var prop = where == "text" ? "textClass"
                : where == "background" ? "bgClass"
                : where == "gutter" ? "gutterClass" : "wrapClass";
       if (!line[prop]) line[prop] = cls;
       else if (classTest(cls).test(line[prop])) return false;
       else line[prop] += " " + cls;
       return true;
     });
   }),
   removeLineClass: docMethodOp(function(handle, where, cls) {
     return changeLine(this, handle, where == "gutter" ? "gutter" : "class", function(line) {
       var prop = where == "text" ? "textClass"
                : where == "background" ? "bgClass"
                : where == "gutter" ? "gutterClass" : "wrapClass";
       var cur = line[prop];
       if (!cur) return false;
       else if (cls == null) line[prop] = null;
       else {
         var found = cur.match(classTest(cls));
         if (!found) return false;
         var end = found.index + found[0].length;
         line[prop] = cur.slice(0, found.index) + (!found.index || end == cur.length ? "" : " ") + cur.slice(end) || null;
       }
       return true;
     });
   }),
   addLineWidget: docMethodOp(function(handle, node, options) {
     return addLineWidget(this, handle, node, options);
   }),
   removeLineWidget: function(widget) { widget.clear(); },
   markText: function(from, to, options) {
     return markText(this, clipPos(this, from), clipPos(this, to), options, "range");
   },
   setBookmark: function(pos, options) {
     var realOpts = {replacedWith: options && (options.nodeType == null ? options.widget : options),
                     insertLeft: options && options.insertLeft,
                     clearWhenEmpty: false, shared: options && options.shared,
                     handleMouseEvents: options && options.handleMouseEvents};
     pos = clipPos(this, pos);
     return markText(this, pos, pos, realOpts, "bookmark");
   },
   findMarksAt: function(pos) {
     pos = clipPos(this, pos);
     var markers = [], spans = getLine(this, pos.line).markedSpans;
     if (spans) for (var i = 0; i < spans.length; ++i) {
       var span = spans[i];
       if ((span.from == null || span.from <= pos.ch) &&
           (span.to == null || span.to >= pos.ch))
         markers.push(span.marker.parent || span.marker);
     }
     return markers;
   },
   findMarks: function(from, to, filter) {
     from = clipPos(this, from); to = clipPos(this, to);
     var found = [], lineNo = from.line;
     this.iter(from.line, to.line + 1, function(line) {
       var spans = line.markedSpans;
       if (spans) for (var i = 0; i < spans.length; i++) {
         var span = spans[i];
         if (!(lineNo == from.line && from.ch > span.to ||
               span.from == null && lineNo != from.line||
               lineNo == to.line && span.from > to.ch) &&
             (!filter || filter(span.marker)))
           found.push(span.marker.parent || span.marker);
       }
       ++lineNo;
     });
     return found;
   },
   getAllMarks: function() {
     var markers = [];
     this.iter(function(line) {
       var sps = line.markedSpans;
       if (sps) for (var i = 0; i < sps.length; ++i)
         if (sps[i].from != null) markers.push(sps[i].marker);
     });
     return markers;
   },
   posFromIndex: function(off) {
     var ch, lineNo = this.first;
     this.iter(function(line) {
       var sz = line.text.length + 1;
       if (sz > off) { ch = off; return true; }
       off -= sz;
       ++lineNo;
     });
     return clipPos(this, Pos(lineNo, ch));
   },
   indexFromPos: function (coords) {
     coords = clipPos(this, coords);
     var index = coords.ch;
     if (coords.line < this.first || coords.ch < 0) return 0;
     this.iter(this.first, coords.line, function (line) {
       index += line.text.length + 1;
     });
     return index;
   },
   copy: function(copyHistory) {
     var doc = new Doc(getLines(this, this.first, this.first + this.size),
                       this.modeOption, this.first, this.lineSep);
     doc.scrollTop = this.scrollTop; doc.scrollLeft = this.scrollLeft;
     doc.sel = this.sel;
     doc.extend = false;
     if (copyHistory) {
       doc.history.undoDepth = this.history.undoDepth;
       doc.setHistory(this.getHistory());
     }
     return doc;
   },
   linkedDoc: function(options) {
     if (!options) options = {};
     var from = this.first, to = this.first + this.size;
     if (options.from != null && options.from > from) from = options.from;
     if (options.to != null && options.to < to) to = options.to;
     var copy = new Doc(getLines(this, from, to), options.mode || this.modeOption, from, this.lineSep);
     if (options.sharedHist) copy.history = this.history;
     (this.linked || (this.linked = [])).push({doc: copy, sharedHist: options.sharedHist});
     copy.linked = [{doc: this, isParent: true, sharedHist: options.sharedHist}];
     copySharedMarkers(copy, findSharedMarkers(this));
     return copy;
   },
   unlinkDoc: function(other) {
     if (other instanceof CodeMirror) other = other.doc;
     if (this.linked) for (var i = 0; i < this.linked.length; ++i) {
       var link = this.linked[i];
       if (link.doc != other) continue;
       this.linked.splice(i, 1);
       other.unlinkDoc(this);
       detachSharedMarkers(findSharedMarkers(this));
       break;
     }
     // If the histories were shared, split them again
     if (other.history == this.history) {
       var splitIds = [other.id];
       linkedDocs(other, function(doc) {splitIds.push(doc.id);}, true);
       other.history = new History(null);
       other.history.done = copyHistoryArray(this.history.done, splitIds);
       other.history.undone = copyHistoryArray(this.history.undone, splitIds);
     }
   },
   iterLinkedDocs: function(f) {linkedDocs(this, f);},
   getMode: function() {return this.mode;},
   getEditor: function() {return this.cm;},
   splitLines: function(str) {
     if (this.lineSep) return str.split(this.lineSep);
     return splitLinesAuto(str);
   },
   lineSeparator: function() { return this.lineSep || "\n"; }
 });
 // Public alias.
 Doc.prototype.eachLine = Doc.prototype.iter;
 // Set up methods on CodeMirror's prototype to redirect to the editor's document.
 var dontDelegate = "iter insert remove copy getEditor constructor".split(" ");
 for (var prop in Doc.prototype) if (Doc.prototype.hasOwnProperty(prop) && indexOf(dontDelegate, prop) < 0)
   CodeMirror.prototype[prop] = (function(method) {
     return function() {return method.apply(this.doc, arguments);};
   })(Doc.prototype[prop]);
 eventMixin(Doc);
 // Call f for all linked documents.
 function linkedDocs(doc, f, sharedHistOnly) {
   function propagate(doc, skip, sharedHist) {
     if (doc.linked) for (var i = 0; i < doc.linked.length; ++i) {
       var rel = doc.linked[i];
       if (rel.doc == skip) continue;
       var shared = sharedHist && rel.sharedHist;
       if (sharedHistOnly && !shared) continue;
       f(rel.doc, shared);
       propagate(rel.doc, doc, shared);
     }
   }
   propagate(doc, null, true);
 }
 // Attach a document to an editor.
 function attachDoc(cm, doc) {
   if (doc.cm) throw new Error("This document is already in use.");
   cm.doc = doc;
   doc.cm = cm;
   estimateLineHeights(cm);
   loadMode(cm);
   if (!cm.options.lineWrapping) findMaxLine(cm);
   cm.options.mode = doc.modeOption;
   regChange(cm);
 }
 // LINE UTILITIES
 // Find the line object corresponding to the given line number.
 function getLine(doc, n) {
   n -= doc.first;
   if (n < 0 || n >= doc.size) throw new Error("There is no line " + (n + doc.first) + " in the document.");
   for (var chunk = doc; !chunk.lines;) {
     for (var i = 0;; ++i) {
       var child = chunk.children[i], sz = child.chunkSize();
       if (n < sz) { chunk = child; break; }
       n -= sz;
     }
   }
   return chunk.lines[n];
 }
 // Get the part of a document between two positions, as an array of
 // strings.
 function getBetween(doc, start, end) {
   var out = [], n = start.line;
   doc.iter(start.line, end.line + 1, function(line) {
     var text = line.text;
     if (n == end.line) text = text.slice(0, end.ch);
     if (n == start.line) text = text.slice(start.ch);
     out.push(text);
     ++n;
   });
   return out;
 }
 // Get the lines between from and to, as array of strings.
 function getLines(doc, from, to) {
   var out = [];
   doc.iter(from, to, function(line) { out.push(line.text); });
   return out;
 }
 // Update the height of a line, propagating the height change
 // upwards to parent nodes.
 function updateLineHeight(line, height) {
   var diff = height - line.height;
   if (diff) for (var n = line; n; n = n.parent) n.height += diff;
 }
 // Given a line object, find its line number by walking up through
 // its parent links.
 function lineNo(line) {
   if (line.parent == null) return null;
   var cur = line.parent, no = indexOf(cur.lines, line);
   for (var chunk = cur.parent; chunk; cur = chunk, chunk = chunk.parent) {
     for (var i = 0;; ++i) {
       if (chunk.children[i] == cur) break;
       no += chunk.children[i].chunkSize();
     }
   }
   return no + cur.first;
 }
 // Find the line at the given vertical position, using the height
 // information in the document tree.
 function lineAtHeight(chunk, h) {
   var n = chunk.first;
   outer: do {
     for (var i = 0; i < chunk.children.length; ++i) {
       var child = chunk.children[i], ch = child.height;
       if (h < ch) { chunk = child; continue outer; }
       h -= ch;
       n += child.chunkSize();
     }
     return n;
   } while (!chunk.lines);
   for (var i = 0; i < chunk.lines.length; ++i) {
     var line = chunk.lines[i], lh = line.height;
     if (h < lh) break;
     h -= lh;
   }
   return n + i;
 }


 // Find the height above the given line.
 function heightAtLine(lineObj) {
   lineObj = visualLine(lineObj);
   var h = 0, chunk = lineObj.parent;
   for (var i = 0; i < chunk.lines.length; ++i) {
     var line = chunk.lines[i];
     if (line == lineObj) break;
     else h += line.height;
   }
   for (var p = chunk.parent; p; chunk = p, p = chunk.parent) {
     for (var i = 0; i < p.children.length; ++i) {
       var cur = p.children[i];
       if (cur == chunk) break;
       else h += cur.height;
     }
   }
   return h;
 }
 // Get the bidi ordering for the given line (and cache it). Returns
 // false for lines that are fully left-to-right, and an array of
 // BidiSpan objects otherwise.
 function getOrder(line) {
   var order = line.order;
   if (order == null) order = line.order = bidiOrdering(line.text);
   return order;
 }
 // HISTORY
 function History(startGen) {
   // Arrays of change events and selections. Doing something adds an
   // event to done and clears undo. Undoing moves events from done
   // to undone, redoing moves them in the other direction.
   this.done = []; this.undone = [];
   this.undoDepth = Infinity;
   // Used to track when changes can be merged into a single undo
   // event
   this.lastModTime = this.lastSelTime = 0;
   this.lastOp = this.lastSelOp = null;
   this.lastOrigin = this.lastSelOrigin = null;
   // Used by the isClean() method
   this.generation = this.maxGeneration = startGen || 1;
 }
 // Create a history change event from an updateDoc-style change
 // object.
 function historyChangeFromChange(doc, change) {
   var histChange = {from: copyPos(change.from), to: changeEnd(change), text: getBetween(doc, change.from, change.to)};
   attachLocalSpans(doc, histChange, change.from.line, change.to.line + 1);
   linkedDocs(doc, function(doc) {attachLocalSpans(doc, histChange, change.from.line, change.to.line + 1);}, true);
   return histChange;
 }
 // Pop all selection events off the end of a history array. Stop at
 // a change event.
 function clearSelectionEvents(array) {
   while (array.length) {
     var last = lst(array);
     if (last.ranges) array.pop();
     else break;
   }
 }
 // Find the top change event in the history. Pop off selection
 // events that are in the way.
 function lastChangeEvent(hist, force) {
   if (force) {
     clearSelectionEvents(hist.done);
     return lst(hist.done);
   } else if (hist.done.length && !lst(hist.done).ranges) {
     return lst(hist.done);
   } else if (hist.done.length > 1 && !hist.done[hist.done.length - 2].ranges) {
     hist.done.pop();
     return lst(hist.done);
   }
 }
 // Register a change in the history. Merges changes that are within
 // a single operation, ore are close together with an origin that
 // allows merging (starting with "+") into a single event.
 function addChangeToHistory(doc, change, selAfter, opId) {
   var hist = doc.history;
   hist.undone.length = 0;
   var time = +new Date, cur;
   if ((hist.lastOp == opId ||
        hist.lastOrigin == change.origin && change.origin &&
        ((change.origin.charAt(0) == "+" && doc.cm && hist.lastModTime > time - doc.cm.options.historyEventDelay) ||
         change.origin.charAt(0) == "*")) &&
       (cur = lastChangeEvent(hist, hist.lastOp == opId))) {
     // Merge this change into the last event
     var last = lst(cur.changes);
     if (cmp(change.from, change.to) == 0 && cmp(change.from, last.to) == 0) {
       // Optimized case for simple insertion -- don't want to add
       // new changesets for every character typed
       last.to = changeEnd(change);
     } else {
       // Add new sub-event
       cur.changes.push(historyChangeFromChange(doc, change));
     }
   } else {
     // Can not be merged, start a new event.
     var before = lst(hist.done);
     if (!before || !before.ranges)
       pushSelectionToHistory(doc.sel, hist.done);
     cur = {changes: [historyChangeFromChange(doc, change)],
            generation: hist.generation};
     hist.done.push(cur);
     while (hist.done.length > hist.undoDepth) {
       hist.done.shift();
       if (!hist.done[0].ranges) hist.done.shift();
     }
   }
   hist.done.push(selAfter);
   hist.generation = ++hist.maxGeneration;
   hist.lastModTime = hist.lastSelTime = time;
   hist.lastOp = hist.lastSelOp = opId;
   hist.lastOrigin = hist.lastSelOrigin = change.origin;
   if (!last) signal(doc, "historyAdded");
 }
 function selectionEventCanBeMerged(doc, origin, prev, sel) {
   var ch = origin.charAt(0);
   return ch == "*" ||
     ch == "+" &&
     prev.ranges.length == sel.ranges.length &&
     prev.somethingSelected() == sel.somethingSelected() &&
     new Date - doc.history.lastSelTime <= (doc.cm ? doc.cm.options.historyEventDelay : 500);
 }
 // Called whenever the selection changes, sets the new selection as
 // the pending selection in the history, and pushes the old pending
 // selection into the 'done' array when it was significantly
 // different (in number of selected ranges, emptiness, or time).
 function addSelectionToHistory(doc, sel, opId, options) {
   var hist = doc.history, origin = options && options.origin;
   // A new event is started when the previous origin does not match
   // the current, or the origins don't allow matching. Origins
   // starting with * are always merged, those starting with + are
   // merged when similar and close together in time.
   if (opId == hist.lastSelOp ||
       (origin && hist.lastSelOrigin == origin &&
        (hist.lastModTime == hist.lastSelTime && hist.lastOrigin == origin ||
         selectionEventCanBeMerged(doc, origin, lst(hist.done), sel))))
     hist.done[hist.done.length - 1] = sel;
   else
     pushSelectionToHistory(sel, hist.done);
   hist.lastSelTime = +new Date;
   hist.lastSelOrigin = origin;
   hist.lastSelOp = opId;
   if (options && options.clearRedo !== false)
     clearSelectionEvents(hist.undone);
 }
 function pushSelectionToHistory(sel, dest) {
   var top = lst(dest);
   if (!(top && top.ranges && top.equals(sel)))
     dest.push(sel);
 }
 // Used to store marked span information in the history.
 function attachLocalSpans(doc, change, from, to) {
   var existing = change["spans_" + doc.id], n = 0;
   doc.iter(Math.max(doc.first, from), Math.min(doc.first + doc.size, to), function(line) {
     if (line.markedSpans)
       (existing || (existing = change["spans_" + doc.id] = {}))[n] = line.markedSpans;
     ++n;
   });
 }
 // When un/re-doing restores text containing marked spans, those
 // that have been explicitly cleared should not be restored.
 function removeClearedSpans(spans) {
   if (!spans) return null;
   for (var i = 0, out; i < spans.length; ++i) {
     if (spans[i].marker.explicitlyCleared) { if (!out) out = spans.slice(0, i); }
     else if (out) out.push(spans[i]);
   }
   return !out ? spans : out.length ? out : null;
 }
 // Retrieve and filter the old marked spans stored in a change event.
 function getOldSpans(doc, change) {
   var found = change["spans_" + doc.id];
   if (!found) return null;
   for (var i = 0, nw = []; i < change.text.length; ++i)
     nw.push(removeClearedSpans(found[i]));
   return nw;
 }
 // Used both to provide a JSON-safe object in .getHistory, and, when
 // detaching a document, to split the history in two
 function copyHistoryArray(events, newGroup, instantiateSel) {
   for (var i = 0, copy = []; i < events.length; ++i) {
     var event = events[i];
     if (event.ranges) {
       copy.push(instantiateSel ? Selection.prototype.deepCopy.call(event) : event);
       continue;
     }
     var changes = event.changes, newChanges = [];
     copy.push({changes: newChanges});
     for (var j = 0; j < changes.length; ++j) {
       var change = changes[j], m;
       newChanges.push({from: change.from, to: change.to, text: change.text});
       if (newGroup) for (var prop in change) if (m = prop.match(/^spans_(\d+)$/)) {
         if (indexOf(newGroup, Number(m[1])) > -1) {
           lst(newChanges)[prop] = change[prop];
           delete change[prop];
         }
       }
     }
   }
   return copy;
 }
 // Rebasing/resetting history to deal with externally-sourced changes
 function rebaseHistSelSingle(pos, from, to, diff) {
   if (to < pos.line) {
     pos.line += diff;
   } else if (from < pos.line) {
     pos.line = from;
     pos.ch = 0;
   }
 }
 // Tries to rebase an array of history events given a change in the
 // document. If the change touches the same lines as the event, the
 // event, and everything 'behind' it, is discarded. If the change is
 // before the event, the event's positions are updated. Uses a
 // copy-on-write scheme for the positions, to avoid having to
 // reallocate them all on every rebase, but also avoid problems with
 // shared position objects being unsafely updated.
 function rebaseHistArray(array, from, to, diff) {
   for (var i = 0; i < array.length; ++i) {
     var sub = array[i], ok = true;
     if (sub.ranges) {
       if (!sub.copied) { sub = array[i] = sub.deepCopy(); sub.copied = true; }
       for (var j = 0; j < sub.ranges.length; j++) {
         rebaseHistSelSingle(sub.ranges[j].anchor, from, to, diff);
         rebaseHistSelSingle(sub.ranges[j].head, from, to, diff);
       }
       continue;
     }
     for (var j = 0; j < sub.changes.length; ++j) {
       var cur = sub.changes[j];
       if (to < cur.from.line) {
         cur.from = Pos(cur.from.line + diff, cur.from.ch);
         cur.to = Pos(cur.to.line + diff, cur.to.ch);
       } else if (from <= cur.to.line) {
         ok = false;
         break;
       }
     }
     if (!ok) {
       array.splice(0, i + 1);
       i = 0;
     }
   }
 }
 function rebaseHist(hist, change) {
   var from = change.from.line, to = change.to.line, diff = change.text.length - (to - from) - 1;
   rebaseHistArray(hist.done, from, to, diff);
   rebaseHistArray(hist.undone, from, to, diff);
 }
 // EVENT UTILITIES
 // Due to the fact that we still support jurassic IE versions, some
 // compatibility wrappers are needed.
 var e_preventDefault = CodeMirror.e_preventDefault = function(e) {
   if (e.preventDefault) e.preventDefault();
   else e.returnValue = false;
 };
 var e_stopPropagation = CodeMirror.e_stopPropagation = function(e) {
   if (e.stopPropagation) e.stopPropagation();
   else e.cancelBubble = true;
 };
 function e_defaultPrevented(e) {
   return e.defaultPrevented != null ? e.defaultPrevented : e.returnValue == false;
 }
 var e_stop = CodeMirror.e_stop = function(e) {e_preventDefault(e); e_stopPropagation(e);};
 function e_target(e) {return e.target || e.srcElement;}
 function e_button(e) {
   var b = e.which;
   if (b == null) {
     if (e.button & 1) b = 1;
     else if (e.button & 2) b = 3;
     else if (e.button & 4) b = 2;
   }
   if (mac && e.ctrlKey && b == 1) b = 3;
   return b;
 }
 // EVENT HANDLING
 // Lightweight event framework. on/off also work on DOM nodes,
 // registering native DOM handlers.
 var on = CodeMirror.on = function(emitter, type, f) {
   if (emitter.addEventListener)
     emitter.addEventListener(type, f, false);
   else if (emitter.attachEvent)
     emitter.attachEvent("on" + type, f);
   else {
     var map = emitter._handlers || (emitter._handlers = {});
     var arr = map[type] || (map[type] = []);
     arr.push(f);
   }
 };
 var off = CodeMirror.off = function(emitter, type, f) {
   if (emitter.removeEventListener)
     emitter.removeEventListener(type, f, false);
   else if (emitter.detachEvent)
     emitter.detachEvent("on" + type, f);
   else {
     var arr = emitter._handlers && emitter._handlers[type];
     if (!arr) return;
     for (var i = 0; i < arr.length; ++i)
       if (arr[i] == f) { arr.splice(i, 1); break; }
   }
 };
 var signal = CodeMirror.signal = function(emitter, type /*, values...*/) {
   var arr = emitter._handlers && emitter._handlers[type];
   if (!arr) return;
   var args = Array.prototype.slice.call(arguments, 2);
   for (var i = 0; i < arr.length; ++i) arr[i].apply(null, args);
 };
 var orphanDelayedCallbacks = null;
 // Often, we want to signal events at a point where we are in the
 // middle of some work, but don't want the handler to start calling
 // other methods on the editor, which might be in an inconsistent
 // state or simply not expect any other events to happen.
 // signalLater looks whether there are any handlers, and schedules
 // them to be executed when the last operation ends, or, if no
 // operation is active, when a timeout fires.
 function signalLater(emitter, type /*, values...*/) {
   var arr = emitter._handlers && emitter._handlers[type];
   if (!arr) return;
   var args = Array.prototype.slice.call(arguments, 2), list;
   if (operationGroup) {
     list = operationGroup.delayedCallbacks;
   } else if (orphanDelayedCallbacks) {
     list = orphanDelayedCallbacks;
   } else {
     list = orphanDelayedCallbacks = [];
     setTimeout(fireOrphanDelayed, 0);
   }
   function bnd(f) {return function(){f.apply(null, args);};};
   for (var i = 0; i < arr.length; ++i)
     list.push(bnd(arr[i]));
 }
 function fireOrphanDelayed() {
   var delayed = orphanDelayedCallbacks;
   orphanDelayedCallbacks = null;
   for (var i = 0; i < delayed.length; ++i) delayed[i]();
 }
 // The DOM events that CodeMirror handles can be overridden by
 // registering a (non-DOM) handler on the editor for the event name,
 // and preventDefault-ing the event in that handler.
 function signalDOMEvent(cm, e, override) {
   if (typeof e == "string")
     e = {type: e, preventDefault: function() { this.defaultPrevented = true; }};
   signal(cm, override || e.type, cm, e);
   return e_defaultPrevented(e) || e.codemirrorIgnore;
 }
 function signalCursorActivity(cm) {
   var arr = cm._handlers && cm._handlers.cursorActivity;
   if (!arr) return;
   var set = cm.curOp.cursorActivityHandlers || (cm.curOp.cursorActivityHandlers = []);
   for (var i = 0; i < arr.length; ++i) if (indexOf(set, arr[i]) == -1)
     set.push(arr[i]);
 }
 function hasHandler(emitter, type) {
   var arr = emitter._handlers && emitter._handlers[type];
   return arr && arr.length > 0;
 }
 // Add on and off methods to a constructor's prototype, to make
 // registering events on such objects more convenient.
 function eventMixin(ctor) {
   ctor.prototype.on = function(type, f) {on(this, type, f);};
   ctor.prototype.off = function(type, f) {off(this, type, f);};
 }
 // MISC UTILITIES
 // Number of pixels added to scroller and sizer to hide scrollbar
 var scrollerGap = 30;
 // Returned or thrown by various protocols to signal 'I'm not
 // handling this'.
 var Pass = CodeMirror.Pass = {toString: function(){return "CodeMirror.Pass";}};
 // Reused option objects for setSelection & friends
 var sel_dontScroll = {scroll: false}, sel_mouse = {origin: "*mouse"}, sel_move = {origin: "+move"};
 function Delayed() {this.id = null;}
 Delayed.prototype.set = function(ms, f) {
   clearTimeout(this.id);
   this.id = setTimeout(f, ms);
 };
 // Counts the column offset in a string, taking tabs into account.
 // Used mostly to find indentation.
 var countColumn = CodeMirror.countColumn = function(string, end, tabSize, startIndex, startValue) {
   if (end == null) {
     end = string.search(/[^\s\u00a0]/);
     if (end == -1) end = string.length;
   }
   for (var i = startIndex || 0, n = startValue || 0;;) {
     var nextTab = string.indexOf("\t", i);
     if (nextTab < 0 || nextTab >= end)
       return n + (end - i);
     n += nextTab - i;
     n += tabSize - (n % tabSize);
     i = nextTab + 1;
   }
 };
 // The inverse of countColumn -- find the offset that corresponds to
 // a particular column.
 function findColumn(string, goal, tabSize) {
   for (var pos = 0, col = 0;;) {
     var nextTab = string.indexOf("\t", pos);
     if (nextTab == -1) nextTab = string.length;
     var skipped = nextTab - pos;
     if (nextTab == string.length || col + skipped >= goal)
       return pos + Math.min(skipped, goal - col);
     col += nextTab - pos;
     col += tabSize - (col % tabSize);
     pos = nextTab + 1;
     if (col >= goal) return pos;
   }
 }
 var spaceStrs = [""];
 function spaceStr(n) {
   while (spaceStrs.length <= n)
     spaceStrs.push(lst(spaceStrs) + " ");
   return spaceStrs[n];
 }
 function lst(arr) { return arr[arr.length-1]; }
 var selectInput = function(node) { node.select(); };
 if (ios) // Mobile Safari apparently has a bug where select() is broken.
   selectInput = function(node) { node.selectionStart = 0; node.selectionEnd = node.value.length; };
 else if (ie) // Suppress mysterious IE10 errors
   selectInput = function(node) { try { node.select(); } catch(_e) {} };
 function indexOf(array, elt) {
   for (var i = 0; i < array.length; ++i)
     if (array[i] == elt) return i;
   return -1;
 }
 function map(array, f) {
   var out = [];
   for (var i = 0; i < array.length; i++) out[i] = f(array[i], i);
   return out;
 }
 function nothing() {}
 function createObj(base, props) {
   var inst;
   if (Object.create) {
     inst = Object.create(base);
   } else {
     nothing.prototype = base;
     inst = new nothing();
   }
   if (props) copyObj(props, inst);
   return inst;
 };
 function copyObj(obj, target, overwrite) {
   if (!target) target = {};
   for (var prop in obj)
     if (obj.hasOwnProperty(prop) && (overwrite !== false || !target.hasOwnProperty(prop)))
       target[prop] = obj[prop];
   return target;
 }
 function bind(f) {
   var args = Array.prototype.slice.call(arguments, 1);
   return function(){return f.apply(null, args);};
 }
 var nonASCIISingleCaseWordChar = /[\u00df\u0587\u0590-\u05f4\u0600-\u06ff\u3040-\u309f\u30a0-\u30ff\u3400-\u4db5\u4e00-\u9fcc\uac00-\ud7af]/;
 var isWordCharBasic = CodeMirror.isWordChar = function(ch) {
   return /\w/.test(ch) || ch > "\x80" &&
     (ch.toUpperCase() != ch.toLowerCase() || nonASCIISingleCaseWordChar.test(ch));
 };
 function isWordChar(ch, helper) {
   if (!helper) return isWordCharBasic(ch);
   if (helper.source.indexOf("\\w") > -1 && isWordCharBasic(ch)) return true;
   return helper.test(ch);
 }
 function isEmpty(obj) {
   for (var n in obj) if (obj.hasOwnProperty(n) && obj[n]) return false;
   return true;
 }
 // Extending unicode characters. A series of a non-extending char +
 // any number of extending chars is treated as a single unit as far
 // as editing and measuring is concerned. This is not fully correct,
 // since some scripts/fonts/browsers also treat other configurations
 // of code points as a group.
 var extendingChars = /[\u0300-\u036f\u0483-\u0489\u0591-\u05bd\u05bf\u05c1\u05c2\u05c4\u05c5\u05c7\u0610-\u061a\u064b-\u065e\u0670\u06d6-\u06dc\u06de-\u06e4\u06e7\u06e8\u06ea-\u06ed\u0711\u0730-\u074a\u07a6-\u07b0\u07eb-\u07f3\u0816-\u0819\u081b-\u0823\u0825-\u0827\u0829-\u082d\u0900-\u0902\u093c\u0941-\u0948\u094d\u0951-\u0955\u0962\u0963\u0981\u09bc\u09be\u09c1-\u09c4\u09cd\u09d7\u09e2\u09e3\u0a01\u0a02\u0a3c\u0a41\u0a42\u0a47\u0a48\u0a4b-\u0a4d\u0a51\u0a70\u0a71\u0a75\u0a81\u0a82\u0abc\u0ac1-\u0ac5\u0ac7\u0ac8\u0acd\u0ae2\u0ae3\u0b01\u0b3c\u0b3e\u0b3f\u0b41-\u0b44\u0b4d\u0b56\u0b57\u0b62\u0b63\u0b82\u0bbe\u0bc0\u0bcd\u0bd7\u0c3e-\u0c40\u0c46-\u0c48\u0c4a-\u0c4d\u0c55\u0c56\u0c62\u0c63\u0cbc\u0cbf\u0cc2\u0cc6\u0ccc\u0ccd\u0cd5\u0cd6\u0ce2\u0ce3\u0d3e\u0d41-\u0d44\u0d4d\u0d57\u0d62\u0d63\u0dca\u0dcf\u0dd2-\u0dd4\u0dd6\u0ddf\u0e31\u0e34-\u0e3a\u0e47-\u0e4e\u0eb1\u0eb4-\u0eb9\u0ebb\u0ebc\u0ec8-\u0ecd\u0f18\u0f19\u0f35\u0f37\u0f39\u0f71-\u0f7e\u0f80-\u0f84\u0f86\u0f87\u0f90-\u0f97\u0f99-\u0fbc\u0fc6\u102d-\u1030\u1032-\u1037\u1039\u103a\u103d\u103e\u1058\u1059\u105e-\u1060\u1071-\u1074\u1082\u1085\u1086\u108d\u109d\u135f\u1712-\u1714\u1732-\u1734\u1752\u1753\u1772\u1773\u17b7-\u17bd\u17c6\u17c9-\u17d3\u17dd\u180b-\u180d\u18a9\u1920-\u1922\u1927\u1928\u1932\u1939-\u193b\u1a17\u1a18\u1a56\u1a58-\u1a5e\u1a60\u1a62\u1a65-\u1a6c\u1a73-\u1a7c\u1a7f\u1b00-\u1b03\u1b34\u1b36-\u1b3a\u1b3c\u1b42\u1b6b-\u1b73\u1b80\u1b81\u1ba2-\u1ba5\u1ba8\u1ba9\u1c2c-\u1c33\u1c36\u1c37\u1cd0-\u1cd2\u1cd4-\u1ce0\u1ce2-\u1ce8\u1ced\u1dc0-\u1de6\u1dfd-\u1dff\u200c\u200d\u20d0-\u20f0\u2cef-\u2cf1\u2de0-\u2dff\u302a-\u302f\u3099\u309a\ua66f-\ua672\ua67c\ua67d\ua6f0\ua6f1\ua802\ua806\ua80b\ua825\ua826\ua8c4\ua8e0-\ua8f1\ua926-\ua92d\ua947-\ua951\ua980-\ua982\ua9b3\ua9b6-\ua9b9\ua9bc\uaa29-\uaa2e\uaa31\uaa32\uaa35\uaa36\uaa43\uaa4c\uaab0\uaab2-\uaab4\uaab7\uaab8\uaabe\uaabf\uaac1\uabe5\uabe8\uabed\udc00-\udfff\ufb1e\ufe00-\ufe0f\ufe20-\ufe26\uff9e\uff9f]/;
 function isExtendingChar(ch) { return ch.charCodeAt(0) >= 768 && extendingChars.test(ch); }
 // DOM UTILITIES
 function elt(tag, content, className, style) {
   var e = document.createElement(tag);
   if (className) e.className = className;
   if (style) e.style.cssText = style;
   if (typeof content == "string") e.appendChild(document.createTextNode(content));
   else if (content) for (var i = 0; i < content.length; ++i) e.appendChild(content[i]);
   return e;
 }
 var range;
 if (document.createRange) range = function(node, start, end, endNode) {
   var r = document.createRange();
   r.setEnd(endNode || node, end);
   r.setStart(node, start);
   return r;
 };
 else range = function(node, start, end) {
   var r = document.body.createTextRange();
   try { r.moveToElementText(node.parentNode); }
   catch(e) { return r; }
   r.collapse(true);
   r.moveEnd("character", end);
   r.moveStart("character", start);
   return r;
 };
 function removeChildren(e) {
   for (var count = e.childNodes.length; count > 0; --count)
     e.removeChild(e.firstChild);
   return e;
 }
 function removeChildrenAndAdd(parent, e) {
   return removeChildren(parent).appendChild(e);
 }
 var contains = CodeMirror.contains = function(parent, child) {
   if (child.nodeType == 3) // Android browser always returns false when child is a textnode
     child = child.parentNode;
   if (parent.contains)
     return parent.contains(child);
   do {
     if (child.nodeType == 11) child = child.host;
     if (child == parent) return true;
   } while (child = child.parentNode);
 };
 function activeElt() {
   var activeElement = document.activeElement;
   while (activeElement && activeElement.root && activeElement.root.activeElement)
     activeElement = activeElement.root.activeElement;
   return activeElement;
 }
 // Older versions of IE throws unspecified error when touching
 // document.activeElement in some cases (during loading, in iframe)
 if (ie && ie_version < 11) activeElt = function() {
   try { return document.activeElement; }
   catch(e) { return document.body; }
 };
 function classTest(cls) { return new RegExp("(^|\\s)" + cls + "(?:$|\\s)\\s*"); }
 var rmClass = CodeMirror.rmClass = function(node, cls) {
   var current = node.className;
   var match = classTest(cls).exec(current);
   if (match) {
     var after = current.slice(match.index + match[0].length);
     node.className = current.slice(0, match.index) + (after ? match[1] + after : "");
   }
 };
 var addClass = CodeMirror.addClass = function(node, cls) {
   var current = node.className;
   if (!classTest(cls).test(current)) node.className += (current ? " " : "") + cls;
 };
 function joinClasses(a, b) {
   var as = a.split(" ");
   for (var i = 0; i < as.length; i++)
     if (as[i] && !classTest(as[i]).test(b)) b += " " + as[i];
   return b;
 }
 // WINDOW-WIDE EVENTS
 // These must be handled carefully, because naively registering a
 // handler for each editor will cause the editors to never be
 // garbage collected.
 function forEachCodeMirror(f) {
   if (!document.body.getElementsByClassName) return;
   var byClass = document.body.getElementsByClassName("CodeMirror");
   for (var i = 0; i < byClass.length; i++) {
     var cm = byClass[i].CodeMirror;
     if (cm) f(cm);
   }
 }
 var globalsRegistered = false;
 function ensureGlobalHandlers() {
   if (globalsRegistered) return;
   registerGlobalHandlers();
   globalsRegistered = true;
 }
 function registerGlobalHandlers() {
   // When the window resizes, we need to refresh active editors.
   var resizeTimer;
   on(window, "resize", function() {
     if (resizeTimer == null) resizeTimer = setTimeout(function() {
       resizeTimer = null;
       forEachCodeMirror(onResize);
     }, 100);
   });
   // When the window loses focus, we want to show the editor as blurred
   on(window, "blur", function() {
     forEachCodeMirror(onBlur);
   });
 }
 // FEATURE DETECTION
 // Detect drag-and-drop
 var dragAndDrop = function() {
   // There is *some* kind of drag-and-drop support in IE6-8, but I
   // couldn't get it to work yet.
   if (ie && ie_version < 9) return false;
   var div = elt('div');
   return "draggable" in div || "dragDrop" in div;
 }();
 var zwspSupported;
 function zeroWidthElement(measure) {
   if (zwspSupported == null) {
     var test = elt("span", "\u200b");
     removeChildrenAndAdd(measure, elt("span", [test, document.createTextNode("x")]));
     if (measure.firstChild.offsetHeight != 0)
       zwspSupported = test.offsetWidth <= 1 && test.offsetHeight > 2 && !(ie && ie_version < 8);
   }
   var node = zwspSupported ? elt("span", "\u200b") :
     elt("span", "\u00a0", null, "display: inline-block; width: 1px; margin-right: -1px");
   node.setAttribute("cm-text", "");
   return node;
 }
 // Feature-detect IE's crummy client rect reporting for bidi text
 var badBidiRects;
 function hasBadBidiRects(measure) {
   if (badBidiRects != null) return badBidiRects;
   var txt = removeChildrenAndAdd(measure, document.createTextNode("A\u062eA"));
   var r0 = range(txt, 0, 1).getBoundingClientRect();
   if (!r0 || r0.left == r0.right) return false; // Safari returns null in some cases (#2780)
   var r1 = range(txt, 1, 2).getBoundingClientRect();
   return badBidiRects = (r1.right - r0.right < 3);
 }
 // See if "".split is the broken IE version, if so, provide an
 // alternative way to split lines.
 var splitLinesAuto = CodeMirror.splitLines = "\n\nb".split(/\n/).length != 3 ? function(string) {
   var pos = 0, result = [], l = string.length;
   while (pos <= l) {
     var nl = string.indexOf("\n", pos);
     if (nl == -1) nl = string.length;
     var line = string.slice(pos, string.charAt(nl - 1) == "\r" ? nl - 1 : nl);
     var rt = line.indexOf("\r");
     if (rt != -1) {
       result.push(line.slice(0, rt));
       pos += rt + 1;
     } else {
       result.push(line);
       pos = nl + 1;
     }
   }
   return result;
 } : function(string){return string.split(/\r\n?|\n/);};
 var hasSelection = window.getSelection ? function(te) {
   try { return te.selectionStart != te.selectionEnd; }
   catch(e) { return false; }
 } : function(te) {
   try {var range = te.ownerDocument.selection.createRange();}
   catch(e) {}
   if (!range || range.parentElement() != te) return false;
   return range.compareEndPoints("StartToEnd", range) != 0;
 };
 var hasCopyEvent = (function() {
   var e = elt("div");
   if ("oncopy" in e) return true;
   e.setAttribute("oncopy", "return;");
   return typeof e.oncopy == "function";
 })();
 var badZoomedRects = null;
 function hasBadZoomedRects(measure) {
   if (badZoomedRects != null) return badZoomedRects;
   var node = removeChildrenAndAdd(measure, elt("span", "x"));
   var normal = node.getBoundingClientRect();
   var fromRange = range(node, 0, 1).getBoundingClientRect();
   return badZoomedRects = Math.abs(normal.left - fromRange.left) > 1;
 }
 // KEY NAMES
 var keyNames = {3: "Enter", 8: "Backspace", 9: "Tab", 13: "Enter", 16: "Shift", 17: "Ctrl", 18: "Alt",
                 19: "Pause", 20: "CapsLock", 27: "Esc", 32: "Space", 33: "PageUp", 34: "PageDown", 35: "End",
                 36: "Home", 37: "Left", 38: "Up", 39: "Right", 40: "Down", 44: "PrintScrn", 45: "Insert",
                 46: "Delete", 59: ";", 61: "=", 91: "Mod", 92: "Mod", 93: "Mod", 107: "=", 109: "-", 127: "Delete",
                 173: "-", 186: ";", 187: "=", 188: ",", 189: "-", 190: ".", 191: "/", 192: "`", 219: "[", 220: "\\",
                 221: "]", 222: "'", 63232: "Up", 63233: "Down", 63234: "Left", 63235: "Right", 63272: "Delete",
                 63273: "Home", 63275: "End", 63276: "PageUp", 63277: "PageDown", 63302: "Insert"};
 CodeMirror.keyNames = keyNames;
 (function() {
   // Number keys
   for (var i = 0; i < 10; i++) keyNames[i + 48] = keyNames[i + 96] = String(i);
   // Alphabetic keys
   for (var i = 65; i <= 90; i++) keyNames[i] = String.fromCharCode(i);
   // Function keys
   for (var i = 1; i <= 12; i++) keyNames[i + 111] = keyNames[i + 63235] = "F" + i;
 })();
 // BIDI HELPERS
 function iterateBidiSections(order, from, to, f) {
   if (!order) return f(from, to, "ltr");
   var found = false;
   for (var i = 0; i < order.length; ++i) {
     var part = order[i];
     if (part.from < to && part.to > from || from == to && part.to == from) {
       f(Math.max(part.from, from), Math.min(part.to, to), part.level == 1 ? "rtl" : "ltr");
       found = true;
     }
   }
   if (!found) f(from, to, "ltr");
 }
 function bidiLeft(part) { return part.level % 2 ? part.to : part.from; }
 function bidiRight(part) { return part.level % 2 ? part.from : part.to; }
 function lineLeft(line) { var order = getOrder(line); return order ? bidiLeft(order[0]) : 0; }
 function lineRight(line) {
   var order = getOrder(line);
   if (!order) return line.text.length;
   return bidiRight(lst(order));
 }
 function lineStart(cm, lineN) {
   var line = getLine(cm.doc, lineN);
   var visual = visualLine(line);
   if (visual != line) lineN = lineNo(visual);
   var order = getOrder(visual);
   var ch = !order ? 0 : order[0].level % 2 ? lineRight(visual) : lineLeft(visual);
   return Pos(lineN, ch);
 }
 function lineEnd(cm, lineN) {
   var merged, line = getLine(cm.doc, lineN);
   while (merged = collapsedSpanAtEnd(line)) {
     line = merged.find(1, true).line;
     lineN = null;
   }
   var order = getOrder(line);
   var ch = !order ? line.text.length : order[0].level % 2 ? lineLeft(line) : lineRight(line);
   return Pos(lineN == null ? lineNo(line) : lineN, ch);
 }
 function lineStartSmart(cm, pos) {
   var start = lineStart(cm, pos.line);
   var line = getLine(cm.doc, start.line);
   var order = getOrder(line);
   if (!order || order[0].level == 0) {
     var firstNonWS = Math.max(0, line.text.search(/\S/));
     var inWS = pos.line == start.line && pos.ch <= firstNonWS && pos.ch;
     return Pos(start.line, inWS ? 0 : firstNonWS);
   }
   return start;
 }
 function compareBidiLevel(order, a, b) {
   var linedir = order[0].level;
   if (a == linedir) return true;
   if (b == linedir) return false;
   return a < b;
 }
 var bidiOther;
 function getBidiPartAt(order, pos) {
   bidiOther = null;
   for (var i = 0, found; i < order.length; ++i) {
     var cur = order[i];
     if (cur.from < pos && cur.to > pos) return i;
     if ((cur.from == pos || cur.to == pos)) {
       if (found == null) {
         found = i;
       } else if (compareBidiLevel(order, cur.level, order[found].level)) {
         if (cur.from != cur.to) bidiOther = found;
         return i;
       } else {
         if (cur.from != cur.to) bidiOther = i;
         return found;
       }
     }
   }
   return found;
 }
 function moveInLine(line, pos, dir, byUnit) {
   if (!byUnit) return pos + dir;
   do pos += dir;
   while (pos > 0 && isExtendingChar(line.text.charAt(pos)));
   return pos;
 }
 // This is needed in order to move 'visually' through bi-directional
 // text -- i.e., pressing left should make the cursor go left, even
 // when in RTL text. The tricky part is the 'jumps', where RTL and
 // LTR text touch each other. This often requires the cursor offset
 // to move more than one unit, in order to visually move one unit.
 function moveVisually(line, start, dir, byUnit) {
   var bidi = getOrder(line);
   if (!bidi) return moveLogically(line, start, dir, byUnit);
   var pos = getBidiPartAt(bidi, start), part = bidi[pos];
   var target = moveInLine(line, start, part.level % 2 ? -dir : dir, byUnit);
   for (;;) {
     if (target > part.from && target < part.to) return target;
     if (target == part.from || target == part.to) {
       if (getBidiPartAt(bidi, target) == pos) return target;
       part = bidi[pos += dir];
       return (dir > 0) == part.level % 2 ? part.to : part.from;
     } else {
       part = bidi[pos += dir];
       if (!part) return null;
       if ((dir > 0) == part.level % 2)
         target = moveInLine(line, part.to, -1, byUnit);
       else
         target = moveInLine(line, part.from, 1, byUnit);
     }
   }
 }
 function moveLogically(line, start, dir, byUnit) {
   var target = start + dir;
   if (byUnit) while (target > 0 && isExtendingChar(line.text.charAt(target))) target += dir;
   return target < 0 || target > line.text.length ? null : target;
 }
 // Bidirectional ordering algorithm
 // See http://unicode.org/reports/tr9/tr9-13.html for the algorithm
 // that this (partially) implements.
 // One-char codes used for character types:
 // L (L):   Left-to-Right
 // R (R):   Right-to-Left
 // r (AL):  Right-to-Left Arabic
 // 1 (EN):  European Number
 // + (ES):  European Number Separator
 // % (ET):  European Number Terminator
 // n (AN):  Arabic Number
 // , (CS):  Common Number Separator
 // m (NSM): Non-Spacing Mark
 // b (BN):  Boundary Neutral
 // s (B):   Paragraph Separator
 // t (S):   Segment Separator
 // w (WS):  Whitespace
 // N (ON):  Other Neutrals
 // Returns null if characters are ordered as they appear
 // (left-to-right), or an array of sections ({from, to, level}
 // objects) in the order in which they occur visually.
 var bidiOrdering = (function() {
   // Character types for codepoints 0 to 0xff
   var lowTypes = "bbbbbbbbbtstwsbbbbbbbbbbbbbbssstwNN%%%NNNNNN,N,N1111111111NNNNNNNLLLLLLLLLLLLLLLLLLLLLLLLLLNNNNNNLLLLLLLLLLLLLLLLLLLLLLLLLLNNNNbbbbbbsbbbbbbbbbbbbbbbbbbbbbbbbbb,N%%%%NNNNLNNNNN%%11NLNNN1LNNNNNLLLLLLLLLLLLLLLLLLLLLLLNLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLN";
   // Character types for codepoints 0x600 to 0x6ff
   var arabicTypes = "rrrrrrrrrrrr,rNNmmmmmmrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrmmmmmmmmmmmmmmrrrrrrrnnnnnnnnnn%nnrrrmrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrmmmmmmmmmmmmmmmmmmmNmmmm";
   function charType(code) {
     if (code <= 0xf7) return lowTypes.charAt(code);
     else if (0x590 <= code && code <= 0x5f4) return "R";
     else if (0x600 <= code && code <= 0x6ed) return arabicTypes.charAt(code - 0x600);
     else if (0x6ee <= code && code <= 0x8ac) return "r";
     else if (0x2000 <= code && code <= 0x200b) return "w";
     else if (code == 0x200c) return "b";
     else return "L";
   }
   var bidiRE = /[\u0590-\u05f4\u0600-\u06ff\u0700-\u08ac]/;
   var isNeutral = /[stwN]/, isStrong = /[LRr]/, countsAsLeft = /[Lb1n]/, countsAsNum = /[1n]/;
   // Browsers seem to always treat the boundaries of block elements as being L.
   var outerType = "L";
   function BidiSpan(level, from, to) {
     this.level = level;
     this.from = from; this.to = to;
   }
   return function(str) {
     if (!bidiRE.test(str)) return false;
     var len = str.length, types = [];
     for (var i = 0, type; i < len; ++i)
       types.push(type = charType(str.charCodeAt(i)));
     // W1. Examine each non-spacing mark (NSM) in the level run, and
     // change the type of the NSM to the type of the previous
     // character. If the NSM is at the start of the level run, it will
     // get the type of sor.
     for (var i = 0, prev = outerType; i < len; ++i) {
       var type = types[i];
       if (type == "m") types[i] = prev;
       else prev = type;
     }
     // W2. Search backwards from each instance of a European number
     // until the first strong type (R, L, AL, or sor) is found. If an
     // AL is found, change the type of the European number to Arabic
     // number.
     // W3. Change all ALs to R.
     for (var i = 0, cur = outerType; i < len; ++i) {
       var type = types[i];
       if (type == "1" && cur == "r") types[i] = "n";
       else if (isStrong.test(type)) { cur = type; if (type == "r") types[i] = "R"; }
     }
     // W4. A single European separator between two European numbers
     // changes to a European number. A single common separator between
     // two numbers of the same type changes to that type.
     for (var i = 1, prev = types[0]; i < len - 1; ++i) {
       var type = types[i];
       if (type == "+" && prev == "1" && types[i+1] == "1") types[i] = "1";
       else if (type == "," && prev == types[i+1] &&
                (prev == "1" || prev == "n")) types[i] = prev;
       prev = type;
     }
     // W5. A sequence of European terminators adjacent to European
     // numbers changes to all European numbers.
     // W6. Otherwise, separators and terminators change to Other
     // Neutral.
     for (var i = 0; i < len; ++i) {
       var type = types[i];
       if (type == ",") types[i] = "N";
       else if (type == "%") {
         for (var end = i + 1; end < len && types[end] == "%"; ++end) {}
         var replace = (i && types[i-1] == "!") || (end < len && types[end] == "1") ? "1" : "N";
         for (var j = i; j < end; ++j) types[j] = replace;
         i = end - 1;
       }
     }
     // W7. Search backwards from each instance of a European number
     // until the first strong type (R, L, or sor) is found. If an L is
     // found, then change the type of the European number to L.
     for (var i = 0, cur = outerType; i < len; ++i) {
       var type = types[i];
       if (cur == "L" && type == "1") types[i] = "L";
       else if (isStrong.test(type)) cur = type;
     }
     // N1. A sequence of neutrals takes the direction of the
     // surrounding strong text if the text on both sides has the same
     // direction. European and Arabic numbers act as if they were R in
     // terms of their influence on neutrals. Start-of-level-run (sor)
     // and end-of-level-run (eor) are used at level run boundaries.
     // N2. Any remaining neutrals take the embedding direction.
     for (var i = 0; i < len; ++i) {
       if (isNeutral.test(types[i])) {
         for (var end = i + 1; end < len && isNeutral.test(types[end]); ++end) {}
         var before = (i ? types[i-1] : outerType) == "L";
         var after = (end < len ? types[end] : outerType) == "L";
         var replace = before || after ? "L" : "R";
         for (var j = i; j < end; ++j) types[j] = replace;
         i = end - 1;
       }
     }
     // Here we depart from the documented algorithm, in order to avoid
     // building up an actual levels array. Since there are only three
     // levels (0, 1, 2) in an implementation that doesn't take
     // explicit embedding into account, we can build up the order on
     // the fly, without following the level-based algorithm.
     var order = [], m;
     for (var i = 0; i < len;) {
       if (countsAsLeft.test(types[i])) {
         var start = i;
         for (++i; i < len && countsAsLeft.test(types[i]); ++i) {}
         order.push(new BidiSpan(0, start, i));
       } else {
         var pos = i, at = order.length;
         for (++i; i < len && types[i] != "L"; ++i) {}
         for (var j = pos; j < i;) {
           if (countsAsNum.test(types[j])) {
             if (pos < j) order.splice(at, 0, new BidiSpan(1, pos, j));
             var nstart = j;
             for (++j; j < i && countsAsNum.test(types[j]); ++j) {}
             order.splice(at, 0, new BidiSpan(2, nstart, j));
             pos = j;
           } else ++j;
         }
         if (pos < i) order.splice(at, 0, new BidiSpan(1, pos, i));
       }
     }
     if (order[0].level == 1 && (m = str.match(/^\s+/))) {
       order[0].from = m[0].length;
       order.unshift(new BidiSpan(0, 0, m[0].length));
     }
     if (lst(order).level == 1 && (m = str.match(/\s+$/))) {
       lst(order).to -= m[0].length;
       order.push(new BidiSpan(0, len - m[0].length, len));
     }
     if (order[0].level == 2)
       order.unshift(new BidiSpan(1, order[0].to, order[0].to));
     if (order[0].level != lst(order).level)
       order.push(new BidiSpan(order[0].level, len, len));
     return order;
   };
 })();
 // THE END
 CodeMirror.version = "5.6.0";
 return CodeMirror;

});