handling explicitly provided modes from kernelspec.language_info

IPython/html/static/base/js/utils.js

@@ -1,862 +1,860
 // Copyright (c) IPython Development Team.
 // Distributed under the terms of the Modified BSD License.
 
 define([
     'base/js/namespace',
     'jquery',
     'codemirror/lib/codemirror',
     // silently upgrades CodeMirror
     'codemirror/mode/meta',
 ], function(IPython, $, CodeMirror){
     "use strict";
     
     IPython.load_extensions = function () {
         // load one or more IPython notebook extensions with requirejs
         
         var extensions = [];
         var extension_names = arguments;
         for (var i = 0; i < extension_names.length; i++) {
             extensions.push("nbextensions/" + arguments[i]);
         }
         
         require(extensions,
             function () {
                 for (var i = 0; i < arguments.length; i++) {
                     var ext = arguments[i];
                     var ext_name = extension_names[i];
                     // success callback
                     console.log("Loaded extension: " + ext_name);
                     if (ext && ext.load_ipython_extension !== undefined) {
                         ext.load_ipython_extension();
                     }
                 }
             },
             function (err) {
                 // failure callback
                 console.log("Failed to load extension(s):", err.requireModules, err);
             }
         );
     };
 
     //============================================================================
     // Cross-browser RegEx Split
     //============================================================================
 
     // This code has been MODIFIED from the code licensed below to not replace the
     // default browser split.  The license is reproduced here.
 
     // see http://blog.stevenlevithan.com/archives/cross-browser-split for more info:
     /*!
      * Cross-Browser Split 1.1.1
      * Copyright 2007-2012 Steven Levithan <stevenlevithan.com>
      * Available under the MIT License
      * ECMAScript compliant, uniform cross-browser split method
      */
 
     /**
      * Splits a string into an array of strings using a regex or string
      * separator. Matches of the separator are not included in the result array.
      * However, if `separator` is a regex that contains capturing groups,
      * backreferences are spliced into the result each time `separator` is
      * matched. Fixes browser bugs compared to the native
      * `String.prototype.split` and can be used reliably cross-browser.
      * @param {String} str String to split.
      * @param {RegExp|String} separator Regex or string to use for separating
      *     the string.
      * @param {Number} [limit] Maximum number of items to include in the result
      *     array.
      * @returns {Array} Array of substrings.
      * @example
      *
      * // Basic use
      * regex_split('a b c d', ' ');
      * // -> ['a', 'b', 'c', 'd']
      *
      * // With limit
      * regex_split('a b c d', ' ', 2);
      * // -> ['a', 'b']
      *
      * // Backreferences in result array
      * regex_split('..word1 word2..', /([a-z]+)(\d+)/i);
      * // -> ['..', 'word', '1', ' ', 'word', '2', '..']
      */
     var regex_split = function (str, separator, limit) {
         // If `separator` is not a regex, use `split`
         if (Object.prototype.toString.call(separator) !== "[object RegExp]") {
             return split.call(str, separator, limit);
         }
         var output = [],
             flags = (separator.ignoreCase ? "i" : "") +
                     (separator.multiline  ? "m" : "") +
                     (separator.extended   ? "x" : "") + // Proposed for ES6
                     (separator.sticky     ? "y" : ""), // Firefox 3+
             lastLastIndex = 0,
             // Make `global` and avoid `lastIndex` issues by working with a copy
             separator = new RegExp(separator.source, flags + "g"),
             separator2, match, lastIndex, lastLength;
         str += ""; // Type-convert
 
         var compliantExecNpcg = typeof(/()??/.exec("")[1]) === "undefined";
         if (!compliantExecNpcg) {
             // Doesn't need flags gy, but they don't hurt
             separator2 = new RegExp("^" + separator.source + "$(?!\\s)", flags);
         }
         /* Values for `limit`, per the spec:
          * If undefined: 4294967295 // Math.pow(2, 32) - 1
          * If 0, Infinity, or NaN: 0
          * If positive number: limit = Math.floor(limit); if (limit > 4294967295) limit -= 4294967296;
          * If negative number: 4294967296 - Math.floor(Math.abs(limit))
          * If other: Type-convert, then use the above rules
          */
         limit = typeof(limit) === "undefined" ?
             -1 >>> 0 : // Math.pow(2, 32) - 1
             limit >>> 0; // ToUint32(limit)
         while (match = separator.exec(str)) {
             // `separator.lastIndex` is not reliable cross-browser
             lastIndex = match.index + match[0].length;
             if (lastIndex > lastLastIndex) {
                 output.push(str.slice(lastLastIndex, match.index));
                 // Fix browsers whose `exec` methods don't consistently return `undefined` for
                 // nonparticipating capturing groups
                 if (!compliantExecNpcg && match.length > 1) {
                     match[0].replace(separator2, function () {
                         for (var i = 1; i < arguments.length - 2; i++) {
                             if (typeof(arguments[i]) === "undefined") {
                                 match[i] = undefined;
                             }
                         }
                     });
                 }
                 if (match.length > 1 && match.index < str.length) {
                     Array.prototype.push.apply(output, match.slice(1));
                 }
                 lastLength = match[0].length;
                 lastLastIndex = lastIndex;
                 if (output.length >= limit) {
                     break;
                 }
             }
             if (separator.lastIndex === match.index) {
                 separator.lastIndex++; // Avoid an infinite loop
             }
         }
         if (lastLastIndex === str.length) {
             if (lastLength || !separator.test("")) {
                 output.push("");
             }
         } else {
             output.push(str.slice(lastLastIndex));
         }
         return output.length > limit ? output.slice(0, limit) : output;
     };
 
     //============================================================================
     // End contributed Cross-browser RegEx Split
     //============================================================================
 
 
     var uuid = function () {
         /**
          * http://www.ietf.org/rfc/rfc4122.txt
          */
         var s = [];
         var hexDigits = "0123456789ABCDEF";
         for (var i = 0; i < 32; i++) {
             s[i] = hexDigits.substr(Math.floor(Math.random() * 0x10), 1);
         }
         s[12] = "4";  // bits 12-15 of the time_hi_and_version field to 0010
         s[16] = hexDigits.substr((s[16] & 0x3) | 0x8, 1);  // bits 6-7 of the clock_seq_hi_and_reserved to 01
 
         var uuid = s.join("");
         return uuid;
     };
 
 
     //Fix raw text to parse correctly in crazy XML
     function xmlencode(string) {
         return string.replace(/\&/g,'&'+'amp;')
             .replace(/</g,'&'+'lt;')
             .replace(/>/g,'&'+'gt;')
             .replace(/\'/g,'&'+'apos;')
             .replace(/\"/g,'&'+'quot;')
             .replace(/`/g,'&'+'#96;');
     }
 
 
     //Map from terminal commands to CSS classes
     var ansi_colormap = {
         "01":"ansibold",
         
         "30":"ansiblack",
         "31":"ansired",
         "32":"ansigreen",
         "33":"ansiyellow",
         "34":"ansiblue",
         "35":"ansipurple",
         "36":"ansicyan",
         "37":"ansigray",
         
         "40":"ansibgblack",
         "41":"ansibgred",
         "42":"ansibggreen",
         "43":"ansibgyellow",
         "44":"ansibgblue",
         "45":"ansibgpurple",
         "46":"ansibgcyan",
         "47":"ansibggray"
     };
     
     function _process_numbers(attrs, numbers) {
         // process ansi escapes
         var n = numbers.shift();
         if (ansi_colormap[n]) {
             if ( ! attrs["class"] ) {
                 attrs["class"] = ansi_colormap[n];
             } else {
                 attrs["class"] += " " + ansi_colormap[n];
             }
         } else if (n == "38" || n == "48") {
             // VT100 256 color or 24 bit RGB
             if (numbers.length < 2) {
                 console.log("Not enough fields for VT100 color", numbers);
                 return;
             }
             
             var index_or_rgb = numbers.shift();
             var r,g,b;
             if (index_or_rgb == "5") {
                 // 256 color
                 var idx = parseInt(numbers.shift());
                 if (idx < 16) {
                     // indexed ANSI
                     // ignore bright / non-bright distinction
                     idx = idx % 8;
                     var ansiclass = ansi_colormap[n[0] + (idx % 8).toString()];
                     if ( ! attrs["class"] ) {
                         attrs["class"] = ansiclass;
                     } else {
                         attrs["class"] += " " + ansiclass;
                     }
                     return;
                 } else if (idx < 232) {
                     // 216 color 6x6x6 RGB
                     idx = idx - 16;
                     b = idx % 6;
                     g = Math.floor(idx / 6) % 6;
                     r = Math.floor(idx / 36) % 6;
                     // convert to rgb
                     r = (r * 51);
                     g = (g * 51);
                     b = (b * 51);
                 } else {
                     // grayscale
                     idx = idx - 231;
                     // it's 1-24 and should *not* include black or white,
                     // so a 26 point scale
                     r = g = b = Math.floor(idx * 256 / 26);
                 }
             } else if (index_or_rgb == "2") {
                 // Simple 24 bit RGB
                 if (numbers.length > 3) {
                     console.log("Not enough fields for RGB", numbers);
                     return;
                 }
                 r = numbers.shift();
                 g = numbers.shift();
                 b = numbers.shift();
             } else {
                 console.log("unrecognized control", numbers);
                 return;
             }
             if (r !== undefined) {
                 // apply the rgb color
                 var line;
                 if (n == "38") {
                     line = "color: ";
                 } else {
                     line = "background-color: ";
                 }
                 line = line + "rgb(" + r + "," + g + "," + b + ");";
                 if ( !attrs.style ) {
                     attrs.style = line;
                 } else {
                     attrs.style += " " + line;
                 }
             }
         }
     }
 
     function ansispan(str) {
         // ansispan function adapted from github.com/mmalecki/ansispan (MIT License)
         // regular ansi escapes (using the table above)
         var is_open = false;
         return str.replace(/\033\[(0?[01]|22|39)?([;\d]+)?m/g, function(match, prefix, pattern) {
             if (!pattern) {
                 // [(01|22|39|)m close spans
                 if (is_open) {
                     is_open = false;
                     return "</span>";
                 } else {
                     return "";
                 }
             } else {
                 is_open = true;
 
                 // consume sequence of color escapes
                 var numbers = pattern.match(/\d+/g);
                 var attrs = {};
                 while (numbers.length > 0) {
                     _process_numbers(attrs, numbers);
                 }
 
                 var span = "<span ";
                 for (var attr in attrs) {
                     var value = attrs[attr];
                     span = span + " " + attr + '="' + attrs[attr] + '"';
                 }
                 return span + ">";
             }
         });
     }
 
     // Transform ANSI color escape codes into HTML <span> tags with css
     // classes listed in the above ansi_colormap object. The actual color used
     // are set in the css file.
     function fixConsole(txt) {
         txt = xmlencode(txt);
         var re = /\033\[([\dA-Fa-f;]*?)m/;
         var opened = false;
         var cmds = [];
         var opener = "";
         var closer = "";
 
         // Strip all ANSI codes that are not color related.  Matches
         // all ANSI codes that do not end with "m".
         var ignored_re = /(?=(\033\[[\d;=]*[a-ln-zA-Z]{1}))\1(?!m)/g;
         txt = txt.replace(ignored_re, "");
         
         // color ansi codes
         txt = ansispan(txt);
         return txt;
     }
 
     // Remove chunks that should be overridden by the effect of
     // carriage return characters
     function fixCarriageReturn(txt) {
         var tmp = txt;
         do {
             txt = tmp;
             tmp = txt.replace(/\r+\n/gm, '\n'); // \r followed by \n --> newline
             tmp = tmp.replace(/^.*\r+/gm, '');  // Other \r --> clear line
         } while (tmp.length < txt.length);
         return txt;
     }
 
     // Locate any URLs and convert them to a anchor tag
     function autoLinkUrls(txt) {
         return txt.replace(/(^|\s)(https?|ftp)(:[^'">\s]+)/gi,
             "$1<a target=\"_blank\" href=\"$2$3\">$2$3</a>");
     }
 
     var points_to_pixels = function (points) {
         /**
          * A reasonably good way of converting between points and pixels.
          */
         var test = $('<div style="display: none; width: 10000pt; padding:0; border:0;"></div>');
         $(body).append(test);
         var pixel_per_point = test.width()/10000;
         test.remove();
         return Math.floor(points*pixel_per_point);
     };
     
     var always_new = function (constructor) {
         /**
          * wrapper around contructor to avoid requiring `var a = new constructor()`
          * useful for passing constructors as callbacks,
          * not for programmer laziness.
          * from http://programmers.stackexchange.com/questions/118798
          */
         return function () {
             var obj = Object.create(constructor.prototype);
             constructor.apply(obj, arguments);
             return obj;
         };
     };
 
     var url_path_join = function () {
         /**
          * join a sequence of url components with '/'
          */
         var url = '';
         for (var i = 0; i < arguments.length; i++) {
             if (arguments[i] === '') {
                 continue;
             }
             if (url.length > 0 && url[url.length-1] != '/') {
                 url = url + '/' + arguments[i];
             } else {
                 url = url + arguments[i];
             }
         }
         url = url.replace(/\/\/+/, '/');
         return url;
     };
     
     var url_path_split = function (path) {
         /**
          * Like os.path.split for URLs.
          * Always returns two strings, the directory path and the base filename
          */
         
         var idx = path.lastIndexOf('/');
         if (idx === -1) {
             return ['', path];
         } else {
             return [ path.slice(0, idx), path.slice(idx + 1) ];
         }
     };
     
     var parse_url = function (url) {
         /**
          * an `a` element with an href allows attr-access to the parsed segments of a URL
          * a = parse_url("http://localhost:8888/path/name#hash")
          * a.protocol = "http:"
          * a.host     = "localhost:8888"
          * a.hostname = "localhost"
          * a.port     = 8888
          * a.pathname = "/path/name"
          * a.hash     = "#hash"
          */
         var a = document.createElement("a");
         a.href = url;
         return a;
     };
     
     var encode_uri_components = function (uri) {
         /**
          * encode just the components of a multi-segment uri,
          * leaving '/' separators
          */
         return uri.split('/').map(encodeURIComponent).join('/');
     };
     
     var url_join_encode = function () {
         /**
          * join a sequence of url components with '/',
          * encoding each component with encodeURIComponent
          */
         return encode_uri_components(url_path_join.apply(null, arguments));
     };
 
 
     var splitext = function (filename) {
         /**
          * mimic Python os.path.splitext
          * Returns ['base', '.ext']
          */
         var idx = filename.lastIndexOf('.');
         if (idx > 0) {
             return [filename.slice(0, idx), filename.slice(idx)];
         } else {
             return [filename, ''];
         }
     };
 
 
     var escape_html = function (text) {
         /**
          * escape text to HTML
          */
         return $("<div/>").text(text).html();
     };
 
 
     var get_body_data = function(key) {
         /**
          * get a url-encoded item from body.data and decode it
          * we should never have any encoded URLs anywhere else in code
          * until we are building an actual request
          */
         return decodeURIComponent($('body').data(key));
     };
     
     var to_absolute_cursor_pos = function (cm, cursor) {
         /**
          * get the absolute cursor position from CodeMirror's col, ch
          */
         if (!cursor) {
             cursor = cm.getCursor();
         }
         var cursor_pos = cursor.ch;
         for (var i = 0; i < cursor.line; i++) {
             cursor_pos += cm.getLine(i).length + 1;
         }
         return cursor_pos;
     };
     
     var from_absolute_cursor_pos = function (cm, cursor_pos) {
         /**
          * turn absolute cursor postion into CodeMirror col, ch cursor
          */
         var i, line;
         var offset = 0;
         for (i = 0, line=cm.getLine(i); line !== undefined; i++, line=cm.getLine(i)) {
             if (offset + line.length < cursor_pos) {
                 offset += line.length + 1;
             } else {
                 return {
                     line : i,
                     ch : cursor_pos - offset,
                 };
             }
         }
         // reached end, return endpoint
         return {
             ch : line.length - 1,
             line : i - 1,
         };
     };
     
     // http://stackoverflow.com/questions/2400935/browser-detection-in-javascript
     var browser = (function() {
         if (typeof navigator === 'undefined') {
             // navigator undefined in node
             return 'None';
         }
         var N= navigator.appName, ua= navigator.userAgent, tem;
         var M= ua.match(/(opera|chrome|safari|firefox|msie)\/?\s*(\.?\d+(\.\d+)*)/i);
         if (M && (tem= ua.match(/version\/([\.\d]+)/i)) !== null) M[2]= tem[1];
         M= M? [M[1], M[2]]: [N, navigator.appVersion,'-?'];
         return M;
     })();
 
     // http://stackoverflow.com/questions/11219582/how-to-detect-my-browser-version-and-operating-system-using-javascript
     var platform = (function () {
         if (typeof navigator === 'undefined') {
             // navigator undefined in node
             return 'None';
         }
         var OSName="None";
         if (navigator.appVersion.indexOf("Win")!=-1) OSName="Windows";
         if (navigator.appVersion.indexOf("Mac")!=-1) OSName="MacOS";
         if (navigator.appVersion.indexOf("X11")!=-1) OSName="UNIX";
         if (navigator.appVersion.indexOf("Linux")!=-1) OSName="Linux";
         return OSName;
     })();
     
     var get_url_param = function (name) {
         // get a URL parameter. I cannot believe we actually need this.
         // Based on http://stackoverflow.com/a/25359264/938949
         var match = new RegExp('[\?&]' + name + '=([^&]*)').exec(window.location.search);
         if (match){
             return decodeURIComponent(match[1] || '');
         }
     };
     
     var is_or_has = function (a, b) {
         /**
          * Is b a child of a or a itself?
          */
         return a.has(b).length !==0 || a.is(b);
     };
 
     var is_focused = function (e) {
         /**
          * Is element e, or one of its children focused?
          */
         e = $(e);
         var target = $(document.activeElement);
         if (target.length > 0) {
             if (is_or_has(e, target)) {
                 return true;
             } else {
                 return false;
             }
         } else {
             return false;
         }
     };
     
     var mergeopt = function(_class, options, overwrite){
         options = options || {};
         overwrite = overwrite || {};
         return $.extend(true, {}, _class.options_default, options, overwrite);
     };
     
     var ajax_error_msg = function (jqXHR) {
         /**
          * Return a JSON error message if there is one,
          * otherwise the basic HTTP status text.
          */
         if (jqXHR.responseJSON && jqXHR.responseJSON.traceback) {
             return jqXHR.responseJSON.traceback;
         } else if (jqXHR.responseJSON && jqXHR.responseJSON.message) {
             return jqXHR.responseJSON.message;
         } else {
             return jqXHR.statusText;
         }
     };
     var log_ajax_error = function (jqXHR, status, error) {
         /**
          * log ajax failures with informative messages
          */
         var msg = "API request failed (" + jqXHR.status + "): ";
         console.log(jqXHR);
         msg += ajax_error_msg(jqXHR);
         console.log(msg);
     };
 
     var requireCodeMirrorMode = function (mode, callback, errback) {
         /** 
          * find a predefined mode or detect from CM metadata then
          * require and callback with the resolveable mode string: mime or
          * custom name
          */
-        if (typeof mode != "string") mode = mode.name;
 
-        if (CodeMirror.modes.hasOwnProperty(mode)) {
+        var modename = (typeof mode == "string") ? mode :
+            mode.mode || mode.name;
+
+        if (CodeMirror.modes.hasOwnProperty(modename)) {
             callback(mode);
             return;
         }
 
-        var info = CodeMirror.findModeByName(mode) ||
-            CodeMirror.findModeByExtension(mode.split(".").slice(-1)) ||
-            CodeMirror.findModeByMIME(mode);
-
-        if(!info){
-            errback && errback();
-            return;
-        }
+        var info = (mode && mode.mode && mode.mime && mode) ||
+            CodeMirror.findModeByName(modename) ||
+            CodeMirror.findModeByExtension(modename.split(".").slice(-1)) ||
+            CodeMirror.findModeByMIME(modename);
 
         require([
                 // might want to use CodeMirror.modeURL here
                 ['codemirror/mode', info.mode, info.mode].join('/'),
             ], function() { callback(info.mime); }, errback
         );
     };
     
     /** Error type for wrapped XHR errors. */
     var XHR_ERROR = 'XhrError';
     
     /**
      * Wraps an AJAX error as an Error object.
      */
     var wrap_ajax_error = function (jqXHR, status, error) {
         var wrapped_error = new Error(ajax_error_msg(jqXHR));
         wrapped_error.name =  XHR_ERROR;
         // provide xhr response
         wrapped_error.xhr = jqXHR;
         wrapped_error.xhr_status = status;
         wrapped_error.xhr_error = error;
         return wrapped_error;
     };
     
     var promising_ajax = function(url, settings) {
         /**
          * Like $.ajax, but returning an ES6 promise. success and error settings
          * will be ignored.
          */
         settings = settings || {};
         return new Promise(function(resolve, reject) {
             settings.success = function(data, status, jqXHR) {
                 resolve(data);
             };
             settings.error = function(jqXHR, status, error) {
                 log_ajax_error(jqXHR, status, error);
                 reject(wrap_ajax_error(jqXHR, status, error));
             };
             $.ajax(url, settings);
         });
     };
 
     var WrappedError = function(message, error){
         /**
          * Wrappable Error class
          *
          * The Error class doesn't actually act on `this`.  Instead it always
          * returns a new instance of Error.  Here we capture that instance so we
          * can apply it's properties to `this`.
          */
         var tmp = Error.apply(this, [message]);
 
         // Copy the properties of the error over to this.
         var properties = Object.getOwnPropertyNames(tmp);
         for (var i = 0; i < properties.length; i++) {
             this[properties[i]] = tmp[properties[i]];
         }
 
         // Keep a stack of the original error messages.
         if (error instanceof WrappedError) {
             this.error_stack = error.error_stack;
         } else {
             this.error_stack = [error];
         }
         this.error_stack.push(tmp);
 
         return this;
     };
 
     WrappedError.prototype = Object.create(Error.prototype, {});
 
 
     var load_class = function(class_name, module_name, registry) {
         /**
          * Tries to load a class
          *
          * Tries to load a class from a module using require.js, if a module 
          * is specified, otherwise tries to load a class from the global 
          * registry, if the global registry is provided.
          */
         return new Promise(function(resolve, reject) {
 
             // Try loading the view module using require.js
             if (module_name) {
                 require([module_name], function(module) {
                     if (module[class_name] === undefined) {
                         reject(new Error('Class '+class_name+' not found in module '+module_name));
                     } else {
                         resolve(module[class_name]);
                     }
                 }, reject);
             } else {
                 if (registry && registry[class_name]) {
                     resolve(registry[class_name]);
                 } else {
                     reject(new Error('Class '+class_name+' not found in registry '));
                 }
             }
         });
     };
 
     var resolve_promises_dict = function(d) {
         /**
          * Resolve a promiseful dictionary.
          * Returns a single Promise.
          */
         var keys = Object.keys(d);
         var values = [];
         keys.forEach(function(key) {
             values.push(d[key]);
         });
         return Promise.all(values).then(function(v) {
             d = {};
             for(var i=0; i<keys.length; i++) {
                 d[keys[i]] = v[i];
             }
             return d;
         });
     };
 
     var WrappedError = function(message, error){
         /**
          * Wrappable Error class
          *
          * The Error class doesn't actually act on `this`.  Instead it always
          * returns a new instance of Error.  Here we capture that instance so we
          * can apply it's properties to `this`.
          */
         var tmp = Error.apply(this, [message]);
 
         // Copy the properties of the error over to this.
         var properties = Object.getOwnPropertyNames(tmp);
         for (var i = 0; i < properties.length; i++) {
             this[properties[i]] = tmp[properties[i]];
         }
 
         // Keep a stack of the original error messages.
         if (error instanceof WrappedError) {
             this.error_stack = error.error_stack;
         } else {
             this.error_stack = [error];
         }
         this.error_stack.push(tmp);
 
         return this;
     };
 
     WrappedError.prototype = Object.create(Error.prototype, {});
 
     var reject = function(message, log) {
         /**
          * Creates a wrappable Promise rejection function.
          * 
          * Creates a function that returns a Promise.reject with a new WrappedError
          * that has the provided message and wraps the original error that 
          * caused the promise to reject.
          */
         return function(error) { 
             var wrapped_error = new WrappedError(message, error);
             if (log) console.error(wrapped_error); 
             return Promise.reject(wrapped_error); 
         };
     };
 
     var typeset = function(element, text) {
         /**
          * Apply MathJax rendering to an element, and optionally set its text
          *
          * If MathJax is not available, make no changes.
          *
          * Returns the output any number of typeset elements, or undefined if
          * MathJax was not available.
          *
          * Parameters
          * ----------
          * element: Node, NodeList, or jQuery selection
          * text: option string
          */
         if(!window.MathJax){
             return;
         }
         var $el = element.jquery ? element : $(element);
         if(arguments.length > 1){
             $el.text(text);
         }
         return $el.map(function(){
             // MathJax takes a DOM node: $.map makes `this` the context
             return MathJax.Hub.Queue(["Typeset", MathJax.Hub, this]);
         });
     };
 
     var utils = {
         regex_split : regex_split,
         uuid : uuid,
         fixConsole : fixConsole,
         fixCarriageReturn : fixCarriageReturn,
         autoLinkUrls : autoLinkUrls,
         points_to_pixels : points_to_pixels,
         get_body_data : get_body_data,
         parse_url : parse_url,
         url_path_split : url_path_split,
         url_path_join : url_path_join,
         url_join_encode : url_join_encode,
         encode_uri_components : encode_uri_components,
         splitext : splitext,
         escape_html : escape_html,
         always_new : always_new,
         to_absolute_cursor_pos : to_absolute_cursor_pos,
         from_absolute_cursor_pos : from_absolute_cursor_pos,
         browser : browser,
         platform: platform,
         get_url_param: get_url_param,
         is_or_has : is_or_has,
         is_focused : is_focused,
         mergeopt: mergeopt,
         ajax_error_msg : ajax_error_msg,
         log_ajax_error : log_ajax_error,
         requireCodeMirrorMode : requireCodeMirrorMode,
         XHR_ERROR : XHR_ERROR,
         wrap_ajax_error : wrap_ajax_error,
         promising_ajax : promising_ajax,
         WrappedError: WrappedError,
         load_class: load_class,
         resolve_promises_dict: resolve_promises_dict,
         reject: reject,
         typeset: typeset,
     };
 
     // Backwards compatability.
     IPython.utils = utils;
     
     return utils;
 }); 

IPython/html/static/notebook/js/notebook.js

@@ -1,2527 +1,2526
 // Copyright (c) IPython Development Team.
 // Distributed under the terms of the Modified BSD License.
 
 define([
     'base/js/namespace',
     'jquery',
     'base/js/utils',
     'base/js/dialog',
     'notebook/js/cell',
     'notebook/js/textcell',
     'notebook/js/codecell',
     'services/sessions/session',
     'notebook/js/celltoolbar',
     'components/marked/lib/marked',
     'codemirror/lib/codemirror',
     'codemirror/addon/runmode/runmode',
     'notebook/js/mathjaxutils',
     'base/js/keyboard',
     'notebook/js/tooltip',
     'notebook/js/celltoolbarpresets/default',
     'notebook/js/celltoolbarpresets/rawcell',
     'notebook/js/celltoolbarpresets/slideshow',
     'notebook/js/scrollmanager'
 ], function (
     IPython, 
     $,
     utils,
     dialog,
     cellmod,
     textcell,
     codecell,
     session, 
     celltoolbar,
     marked,
     CodeMirror,
     runMode,
     mathjaxutils,
     keyboard,
     tooltip,
     default_celltoolbar,
     rawcell_celltoolbar,
     slideshow_celltoolbar,
     scrollmanager
     ) {
     "use strict";
 
     var Notebook = function (selector, options) {
         /**
          * Constructor
          *
          * A notebook contains and manages cells.
          *
          * Parameters:
          *  selector: string
          *  options: dictionary
          *      Dictionary of keyword arguments.
          *          events: $(Events) instance
          *          keyboard_manager: KeyboardManager instance
          *          contents: Contents instance
          *          save_widget: SaveWidget instance
          *          config: dictionary
          *          base_url : string
          *          notebook_path : string
          *          notebook_name : string
          */
         this.config = utils.mergeopt(Notebook, options.config);
         this.base_url = options.base_url;
         this.notebook_path = options.notebook_path;
         this.notebook_name = options.notebook_name;
         this.events = options.events;
         this.keyboard_manager = options.keyboard_manager;
         this.contents = options.contents;
         this.save_widget = options.save_widget;
         this.tooltip = new tooltip.Tooltip(this.events);
         this.ws_url = options.ws_url;
         this._session_starting = false;
         this.default_cell_type = this.config.default_cell_type || 'code';
 
         //  Create default scroll manager.
         this.scroll_manager = new scrollmanager.ScrollManager(this);
 
         // TODO: This code smells (and the other `= this` line a couple lines down)
         // We need a better way to deal with circular instance references.
         this.keyboard_manager.notebook = this;
         this.save_widget.notebook = this;
         
         mathjaxutils.init();
 
         if (marked) {
             marked.setOptions({
                 gfm : true,
                 tables: true,
                 // FIXME: probably want central config for CodeMirror theme when we have js config
                 langPrefix: "cm-s-ipython language-",
                 highlight: function(code, lang, callback) {
                     if (!lang) {
                         // no language, no highlight
                         if (callback) {
                             callback(null, code);
                             return;
                         } else {
                             return code;
                         }
                     }
                     utils.requireCodeMirrorMode(lang, function (spec) {
                         var el = document.createElement("div");
                         var mode = CodeMirror.getMode({}, spec);
                         if (!mode) {
                             console.log("No CodeMirror mode: " + lang);
                             callback(null, code);
                             return;
                         }
                         try {
                             CodeMirror.runMode(code, spec, el);
                             callback(null, el.innerHTML);
                         } catch (err) {
                             console.log("Failed to highlight " + lang + " code", err);
                             callback(err, code);
                         }
                     }, function (err) {
                         console.log("No CodeMirror mode: " + lang);
                         callback(err, code);
                     });
                 }
             });
         }
 
         this.element = $(selector);
         this.element.scroll();
         this.element.data("notebook", this);
         this.next_prompt_number = 1;
         this.session = null;
         this.kernel = null;
         this.clipboard = null;
         this.undelete_backup = null;
         this.undelete_index = null;
         this.undelete_below = false;
         this.paste_enabled = false;
         this.writable = false;
         // It is important to start out in command mode to match the intial mode
         // of the KeyboardManager.
         this.mode = 'command';
         this.set_dirty(false);
         this.metadata = {};
         this._checkpoint_after_save = false;
         this.last_checkpoint = null;
         this.checkpoints = [];
         this.autosave_interval = 0;
         this.autosave_timer = null;
         // autosave *at most* every two minutes
         this.minimum_autosave_interval = 120000;
         this.notebook_name_blacklist_re = /[\/\\:]/;
         this.nbformat = 4; // Increment this when changing the nbformat
         this.nbformat_minor = this.current_nbformat_minor = 0; // Increment this when changing the nbformat
         this.codemirror_mode = 'ipython';
         this.create_elements();
         this.bind_events();
         this.kernel_selector = null;
         this.dirty = null;
         this.trusted = null;
         this._fully_loaded = false;
 
         // Trigger cell toolbar registration.
         default_celltoolbar.register(this);
         rawcell_celltoolbar.register(this);
         slideshow_celltoolbar.register(this);
 
         // prevent assign to miss-typed properties.
         Object.seal(this);
     };
 
     Notebook.options_default = {
         // can be any cell type, or the special values of
         // 'above', 'below', or 'selected' to get the value from another cell.
         Notebook: {
             default_cell_type: 'code'
         }
     };
 
 
     /**
      * Create an HTML and CSS representation of the notebook.
      * 
      * @method create_elements
      */
     Notebook.prototype.create_elements = function () {
         var that = this;
         this.element.attr('tabindex','-1');
         this.container = $("<div/>").addClass("container").attr("id", "notebook-container");
         // We add this end_space div to the end of the notebook div to:
         // i) provide a margin between the last cell and the end of the notebook
         // ii) to prevent the div from scrolling up when the last cell is being
         // edited, but is too low on the page, which browsers will do automatically.
         var end_space = $('<div/>').addClass('end_space');
         end_space.dblclick(function (e) {
             var ncells = that.ncells();
             that.insert_cell_below('code',ncells-1);
         });
         this.element.append(this.container);
         this.container.append(end_space);
     };
 
     /**
      * Bind JavaScript events: key presses and custom IPython events.
      * 
      * @method bind_events
      */
     Notebook.prototype.bind_events = function () {
         var that = this;
 
         this.events.on('set_next_input.Notebook', function (event, data) {
             if (data.replace) {
                 data.cell.set_text(data.text);
                 data.cell.clear_output();
             } else {
                 var index = that.find_cell_index(data.cell);
                 var new_cell = that.insert_cell_below('code',index);
                 new_cell.set_text(data.text);
             }
             that.dirty = true;
         });
 
         this.events.on('unrecognized_cell.Cell', function () {
             that.warn_nbformat_minor();
         });
 
         this.events.on('unrecognized_output.OutputArea', function () {
             that.warn_nbformat_minor();
         });
 
         this.events.on('set_dirty.Notebook', function (event, data) {
             that.dirty = data.value;
         });
 
         this.events.on('trust_changed.Notebook', function (event, trusted) {
             that.trusted = trusted;
         });
 
         this.events.on('select.Cell', function (event, data) {
             var index = that.find_cell_index(data.cell);
             that.select(index);
         });
 
         this.events.on('edit_mode.Cell', function (event, data) {
             that.handle_edit_mode(data.cell);
         });
 
         this.events.on('command_mode.Cell', function (event, data) {
             that.handle_command_mode(data.cell);
         });
         
         this.events.on('spec_changed.Kernel', function(event, data) {
             that.metadata.kernelspec = 
                 {name: data.name, display_name: data.display_name};
         });
 
         this.events.on('kernel_ready.Kernel', function(event, data) {
             var kinfo = data.kernel.info_reply;
             var langinfo = kinfo.language_info || {};
             that.metadata.language_info = langinfo;
             // Mode 'null' should be plain, unhighlighted text.
             var cm_mode = langinfo.codemirror_mode || langinfo.name || 'null';
             that.set_codemirror_mode(cm_mode);
         });
 
         var collapse_time = function (time) {
             var app_height = $('#ipython-main-app').height(); // content height
             var splitter_height = $('div#pager_splitter').outerHeight(true);
             var new_height = app_height - splitter_height;
             that.element.animate({height : new_height + 'px'}, time);
         };
 
         this.element.bind('collapse_pager', function (event, extrap) {
             var time = (extrap !== undefined) ? ((extrap.duration !== undefined ) ? extrap.duration : 'fast') : 'fast';
             collapse_time(time);
         });
 
         var expand_time = function (time) {
             var app_height = $('#ipython-main-app').height(); // content height
             var splitter_height = $('div#pager_splitter').outerHeight(true);
             var pager_height = $('div#pager').outerHeight(true);
             var new_height = app_height - pager_height - splitter_height;
             that.element.animate({height : new_height + 'px'}, time);
         };
 
         this.element.bind('expand_pager', function (event, extrap) {
             var time = (extrap !== undefined) ? ((extrap.duration !== undefined ) ? extrap.duration : 'fast') : 'fast';
             expand_time(time);
         });
         
         // Firefox 22 broke $(window).on("beforeunload")
         // I'm not sure why or how.
         window.onbeforeunload = function (e) {
             // TODO: Make killing the kernel configurable.
             var kill_kernel = false;
             if (kill_kernel) {
                 that.session.delete();
             }
             // if we are autosaving, trigger an autosave on nav-away.
             // still warn, because if we don't the autosave may fail.
             if (that.dirty) {
                 if ( that.autosave_interval ) {
                     // schedule autosave in a timeout
                     // this gives you a chance to forcefully discard changes
                     // by reloading the page if you *really* want to.
                     // the timer doesn't start until you *dismiss* the dialog.
                     setTimeout(function () {
                         if (that.dirty) {
                             that.save_notebook();
                         }
                     }, 1000);
                     return "Autosave in progress, latest changes may be lost.";
                 } else {
                     return "Unsaved changes will be lost.";
                 }
             }
             // Null is the *only* return value that will make the browser not
             // pop up the "don't leave" dialog.
             return null;
         };
     };
     
     Notebook.prototype.warn_nbformat_minor = function (event) {
         /**
          * trigger a warning dialog about missing functionality from newer minor versions
          */
         var v = 'v' + this.nbformat + '.';
         var orig_vs = v + this.nbformat_minor;
         var this_vs = v + this.current_nbformat_minor;
         var msg = "This notebook is version " + orig_vs + ", but we only fully support up to " +
         this_vs + ".  You can still work with this notebook, but cell and output types " +
         "introduced in later notebook versions will not be available.";
 
         dialog.modal({
             notebook: this,
             keyboard_manager: this.keyboard_manager,
             title : "Newer Notebook",
             body : msg,
             buttons : {
                 OK : {
                     "class" : "btn-danger"
                 }
             }
         });
     }
 
     /**
      * Set the dirty flag, and trigger the set_dirty.Notebook event
      * 
      * @method set_dirty
      */
     Notebook.prototype.set_dirty = function (value) {
         if (value === undefined) {
             value = true;
         }
         if (this.dirty == value) {
             return;
         }
         this.events.trigger('set_dirty.Notebook', {value: value});
     };
 
     /**
      * Scroll the top of the page to a given cell.
      * 
      * @method scroll_to_cell
      * @param {Number} cell_number An index of the cell to view
      * @param {Number} time Animation time in milliseconds
      * @return {Number} Pixel offset from the top of the container
      */
     Notebook.prototype.scroll_to_cell = function (cell_number, time) {
         var cells = this.get_cells();
         time = time || 0;
         cell_number = Math.min(cells.length-1,cell_number);
         cell_number = Math.max(0             ,cell_number);
         var scroll_value = cells[cell_number].element.position().top-cells[0].element.position().top ;
         this.element.animate({scrollTop:scroll_value}, time);
         return scroll_value;
     };
 
     /**
      * Scroll to the bottom of the page.
      * 
      * @method scroll_to_bottom
      */
     Notebook.prototype.scroll_to_bottom = function () {
         this.element.animate({scrollTop:this.element.get(0).scrollHeight}, 0);
     };
 
     /**
      * Scroll to the top of the page.
      * 
      * @method scroll_to_top
      */
     Notebook.prototype.scroll_to_top = function () {
         this.element.animate({scrollTop:0}, 0);
     };
 
     // Edit Notebook metadata
 
     Notebook.prototype.edit_metadata = function () {
         var that = this;
         dialog.edit_metadata({
             md: this.metadata, 
             callback: function (md) {
                 that.metadata = md;
             },
             name: 'Notebook',
             notebook: this,
             keyboard_manager: this.keyboard_manager});
     };
 
     // Cell indexing, retrieval, etc.
 
     /**
      * Get all cell elements in the notebook.
      * 
      * @method get_cell_elements
      * @return {jQuery} A selector of all cell elements
      */
     Notebook.prototype.get_cell_elements = function () {
         return this.container.find(".cell").not('.cell .cell');
     };
 
     /**
      * Get a particular cell element.
      * 
      * @method get_cell_element
      * @param {Number} index An index of a cell to select
      * @return {jQuery} A selector of the given cell.
      */
     Notebook.prototype.get_cell_element = function (index) {
         var result = null;
         var e = this.get_cell_elements().eq(index);
         if (e.length !== 0) {
             result = e;
         }
         return result;
     };
 
     /**
      * Try to get a particular cell by msg_id.
      * 
      * @method get_msg_cell
      * @param {String} msg_id A message UUID
      * @return {Cell} Cell or null if no cell was found.
      */
     Notebook.prototype.get_msg_cell = function (msg_id) {
         return codecell.CodeCell.msg_cells[msg_id] || null;
     };
 
     /**
      * Count the cells in this notebook.
      * 
      * @method ncells
      * @return {Number} The number of cells in this notebook
      */
     Notebook.prototype.ncells = function () {
         return this.get_cell_elements().length;
     };
 
     /**
      * Get all Cell objects in this notebook.
      * 
      * @method get_cells
      * @return {Array} This notebook's Cell objects
      */
     // TODO: we are often calling cells as cells()[i], which we should optimize
     // to cells(i) or a new method.
     Notebook.prototype.get_cells = function () {
         return this.get_cell_elements().toArray().map(function (e) {
             return $(e).data("cell");
         });
     };
 
     /**
      * Get a Cell object from this notebook.
      * 
      * @method get_cell
      * @param {Number} index An index of a cell to retrieve
      * @return {Cell} Cell or null if no cell was found.
      */
     Notebook.prototype.get_cell = function (index) {
         var result = null;
         var ce = this.get_cell_element(index);
         if (ce !== null) {
             result = ce.data('cell');
         }
         return result;
     };
 
     /**
      * Get the cell below a given cell.
      * 
      * @method get_next_cell
      * @param {Cell} cell The provided cell
      * @return {Cell} the next cell or null if no cell was found.
      */
     Notebook.prototype.get_next_cell = function (cell) {
         var result = null;
         var index = this.find_cell_index(cell);
         if (this.is_valid_cell_index(index+1)) {
             result = this.get_cell(index+1);
         }
         return result;
     };
 
     /**
      * Get the cell above a given cell.
      * 
      * @method get_prev_cell
      * @param {Cell} cell The provided cell
      * @return {Cell} The previous cell or null if no cell was found.
      */
     Notebook.prototype.get_prev_cell = function (cell) {
         var result = null;
         var index = this.find_cell_index(cell);
         if (index !== null && index > 0) {
             result = this.get_cell(index-1);
         }
         return result;
     };
     
     /**
      * Get the numeric index of a given cell.
      * 
      * @method find_cell_index
      * @param {Cell} cell The provided cell
      * @return {Number} The cell's numeric index or null if no cell was found.
      */
     Notebook.prototype.find_cell_index = function (cell) {
         var result = null;
         this.get_cell_elements().filter(function (index) {
             if ($(this).data("cell") === cell) {
                 result = index;
             }
         });
         return result;
     };
 
     /**
      * Get a given index , or the selected index if none is provided.
      * 
      * @method index_or_selected
      * @param {Number} index A cell's index
      * @return {Number} The given index, or selected index if none is provided.
      */
     Notebook.prototype.index_or_selected = function (index) {
         var i;
         if (index === undefined || index === null) {
             i = this.get_selected_index();
             if (i === null) {
                 i = 0;
             }
         } else {
             i = index;
         }
         return i;
     };
 
     /**
      * Get the currently selected cell.
      * @method get_selected_cell
      * @return {Cell} The selected cell
      */
     Notebook.prototype.get_selected_cell = function () {
         var index = this.get_selected_index();
         return this.get_cell(index);
     };
 
     /**
      * Check whether a cell index is valid.
      * 
      * @method is_valid_cell_index
      * @param {Number} index A cell index
      * @return True if the index is valid, false otherwise
      */
     Notebook.prototype.is_valid_cell_index = function (index) {
         if (index !== null && index >= 0 && index < this.ncells()) {
             return true;
         } else {
             return false;
         }
     };
 
     /**
      * Get the index of the currently selected cell.
      
      * @method get_selected_index
      * @return {Number} The selected cell's numeric index
      */
     Notebook.prototype.get_selected_index = function () {
         var result = null;
         this.get_cell_elements().filter(function (index) {
             if ($(this).data("cell").selected === true) {
                 result = index;
             }
         });
         return result;
     };
 
 
     // Cell selection.
 
     /**
      * Programmatically select a cell.
      * 
      * @method select
      * @param {Number} index A cell's index
      * @return {Notebook} This notebook
      */
     Notebook.prototype.select = function (index) {
         if (this.is_valid_cell_index(index)) {
             var sindex = this.get_selected_index();
             if (sindex !== null && index !== sindex) {
                 // If we are about to select a different cell, make sure we are
                 // first in command mode.
                 if (this.mode !== 'command') {
                     this.command_mode();
                 }
                 this.get_cell(sindex).unselect();
             }
             var cell = this.get_cell(index);
             cell.select();
             if (cell.cell_type === 'heading') {
                 this.events.trigger('selected_cell_type_changed.Notebook',
                     {'cell_type':cell.cell_type,level:cell.level}
                 );
             } else {
                 this.events.trigger('selected_cell_type_changed.Notebook',
                     {'cell_type':cell.cell_type}
                 );
             }
         }
         return this;
     };
 
     /**
      * Programmatically select the next cell.
      *
      * @method select_next
      * @return {Notebook} This notebook
      */
     Notebook.prototype.select_next = function () {
         var index = this.get_selected_index();
         this.select(index+1);
         return this;
     };
 
     /**
      * Programmatically select the previous cell.
      *
      * @method select_prev
      * @return {Notebook} This notebook
      */
     Notebook.prototype.select_prev = function () {
         var index = this.get_selected_index();
         this.select(index-1);
         return this;
     };
 
 
     // Edit/Command mode
 
     /**
      * Gets the index of the cell that is in edit mode.
      *
      * @method get_edit_index
      *
      * @return index {int}
      **/
     Notebook.prototype.get_edit_index = function () {
         var result = null;
         this.get_cell_elements().filter(function (index) {
             if ($(this).data("cell").mode === 'edit') {
                 result = index;
             }
         });
         return result;
     };
 
     /**
      * Handle when a a cell blurs and the notebook should enter command mode.
      *
      * @method handle_command_mode
      * @param [cell] {Cell} Cell to enter command mode on.
      **/
     Notebook.prototype.handle_command_mode = function (cell) {
         if (this.mode !== 'command') {
             cell.command_mode();
             this.mode = 'command';
             this.events.trigger('command_mode.Notebook');
             this.keyboard_manager.command_mode();
         }
     };
 
     /**
      * Make the notebook enter command mode.
      *
      * @method command_mode
      **/
     Notebook.prototype.command_mode = function () {
         var cell = this.get_cell(this.get_edit_index());
         if (cell && this.mode !== 'command') {
             // We don't call cell.command_mode, but rather call cell.focus_cell()
             // which will blur and CM editor and trigger the call to
             // handle_command_mode.
             cell.focus_cell();
         }
     };
 
     /**
      * Handle when a cell fires it's edit_mode event.
      *
      * @method handle_edit_mode
      * @param [cell] {Cell} Cell to enter edit mode on.
      **/
     Notebook.prototype.handle_edit_mode = function (cell) {
         if (cell && this.mode !== 'edit') {
             cell.edit_mode();
             this.mode = 'edit';
             this.events.trigger('edit_mode.Notebook');
             this.keyboard_manager.edit_mode();
         }
     };
 
     /**
      * Make a cell enter edit mode.
      *
      * @method edit_mode
      **/
     Notebook.prototype.edit_mode = function () {
         var cell = this.get_selected_cell();
         if (cell && this.mode !== 'edit') {
             cell.unrender();
             cell.focus_editor();
         }
     };
 
     /**
      * Focus the currently selected cell.
      *
      * @method focus_cell
      **/
     Notebook.prototype.focus_cell = function () {
         var cell = this.get_selected_cell();
         if (cell === null) {return;}  // No cell is selected
         cell.focus_cell();
     };
 
     // Cell movement
 
     /**
      * Move given (or selected) cell up and select it.
      * 
      * @method move_cell_up
      * @param [index] {integer} cell index
      * @return {Notebook} This notebook
      **/
     Notebook.prototype.move_cell_up = function (index) {
         var i = this.index_or_selected(index);
         if (this.is_valid_cell_index(i) && i > 0) {
             var pivot = this.get_cell_element(i-1);
             var tomove = this.get_cell_element(i);
             if (pivot !== null && tomove !== null) {
                 tomove.detach();
                 pivot.before(tomove);
                 this.select(i-1);
                 var cell = this.get_selected_cell();
                 cell.focus_cell();
             }
             this.set_dirty(true);
         }
         return this;
     };
 
 
     /**
      * Move given (or selected) cell down and select it
      * 
      * @method move_cell_down
      * @param [index] {integer} cell index
      * @return {Notebook} This notebook
      **/
     Notebook.prototype.move_cell_down = function (index) {
         var i = this.index_or_selected(index);
         if (this.is_valid_cell_index(i) && this.is_valid_cell_index(i+1)) {
             var pivot = this.get_cell_element(i+1);
             var tomove = this.get_cell_element(i);
             if (pivot !== null && tomove !== null) {
                 tomove.detach();
                 pivot.after(tomove);
                 this.select(i+1);
                 var cell = this.get_selected_cell();
                 cell.focus_cell();
             }
         }
         this.set_dirty();
         return this;
     };
 
 
     // Insertion, deletion.
 
     /**
      * Delete a cell from the notebook.
      * 
      * @method delete_cell
      * @param [index] A cell's numeric index
      * @return {Notebook} This notebook
      */
     Notebook.prototype.delete_cell = function (index) {
         var i = this.index_or_selected(index);
         var cell = this.get_cell(i);
         if (!cell.is_deletable()) {
             return this;
         }
 
         this.undelete_backup = cell.toJSON();
         $('#undelete_cell').removeClass('disabled');
         if (this.is_valid_cell_index(i)) {
             var old_ncells = this.ncells();
             var ce = this.get_cell_element(i);
             ce.remove();
             if (i === 0) {
                 // Always make sure we have at least one cell.
                 if (old_ncells === 1) {
                     this.insert_cell_below('code');
                 }
                 this.select(0);
                 this.undelete_index = 0;
                 this.undelete_below = false;
             } else if (i === old_ncells-1 && i !== 0) {
                 this.select(i-1);
                 this.undelete_index = i - 1;
                 this.undelete_below = true;
             } else {
                 this.select(i);
                 this.undelete_index = i;
                 this.undelete_below = false;
             }
             this.events.trigger('delete.Cell', {'cell': cell, 'index': i});
             this.set_dirty(true);
         }
         return this;
     };
 
     /**
      * Restore the most recently deleted cell.
      * 
      * @method undelete
      */
     Notebook.prototype.undelete_cell = function() {
         if (this.undelete_backup !== null && this.undelete_index !== null) {
             var current_index = this.get_selected_index();
             if (this.undelete_index < current_index) {
                 current_index = current_index + 1;
             }
             if (this.undelete_index >= this.ncells()) {
                 this.select(this.ncells() - 1);
             }
             else {
                 this.select(this.undelete_index);
             }
             var cell_data = this.undelete_backup;
             var new_cell = null;
             if (this.undelete_below) {
                 new_cell = this.insert_cell_below(cell_data.cell_type);
             } else {
                 new_cell = this.insert_cell_above(cell_data.cell_type);
             }
             new_cell.fromJSON(cell_data);
             if (this.undelete_below) {
                 this.select(current_index+1);
             } else {
                 this.select(current_index);
             }
             this.undelete_backup = null;
             this.undelete_index = null;
         }
         $('#undelete_cell').addClass('disabled');
     };
 
     /**
      * Insert a cell so that after insertion the cell is at given index.
      *
      * If cell type is not provided, it will default to the type of the
      * currently active cell.
      *
      * Similar to insert_above, but index parameter is mandatory
      *
      * Index will be brought back into the accessible range [0,n]
      *
      * @method insert_cell_at_index
      * @param [type] {string} in ['code','markdown', 'raw'], defaults to 'code'
      * @param [index] {int} a valid index where to insert cell
      *
      * @return cell {cell|null} created cell or null
      **/
     Notebook.prototype.insert_cell_at_index = function(type, index){
 
         var ncells = this.ncells();
         index = Math.min(index, ncells);
         index = Math.max(index, 0);
         var cell = null;
         type = type || this.default_cell_type;
         if (type === 'above') {
             if (index > 0) {
                 type = this.get_cell(index-1).cell_type;
             } else {
                 type = 'code';
             }
         } else if (type === 'below') {
             if (index < ncells) {
                 type = this.get_cell(index).cell_type;
             } else {
                 type = 'code';
             }
         } else if (type === 'selected') {
             type = this.get_selected_cell().cell_type;
         }
 
         if (ncells === 0 || this.is_valid_cell_index(index) || index === ncells) {
             var cell_options = {
                 events: this.events, 
                 config: this.config, 
                 keyboard_manager: this.keyboard_manager, 
                 notebook: this,
                 tooltip: this.tooltip
             };
             switch(type) {
             case 'code':
                 cell = new codecell.CodeCell(this.kernel, cell_options);
                 cell.set_input_prompt();
                 break;
             case 'markdown':
                 cell = new textcell.MarkdownCell(cell_options);
                 break;
             case 'raw':
                 cell = new textcell.RawCell(cell_options);
                 break;
             default:
                 console.log("Unrecognized cell type: ", type, cellmod);
                 cell = new cellmod.UnrecognizedCell(cell_options);
             }
 
             if(this._insert_element_at_index(cell.element,index)) {
                 cell.render();
                 this.events.trigger('create.Cell', {'cell': cell, 'index': index});
                 cell.refresh();
                 // We used to select the cell after we refresh it, but there
                 // are now cases were this method is called where select is
                 // not appropriate. The selection logic should be handled by the
                 // caller of the the top level insert_cell methods.
                 this.set_dirty(true);
             }
         }
         return cell;
 
     };
 
     /**
      * Insert an element at given cell index.
      *
      * @method _insert_element_at_index
      * @param element {dom_element} a cell element
      * @param [index] {int} a valid index where to inser cell
      * @private
      *
      * return true if everything whent fine.
      **/
     Notebook.prototype._insert_element_at_index = function(element, index){
         if (element === undefined){
             return false;
         }
 
         var ncells = this.ncells();
 
         if (ncells === 0) {
             // special case append if empty
             this.element.find('div.end_space').before(element);
         } else if ( ncells === index ) {
             // special case append it the end, but not empty
             this.get_cell_element(index-1).after(element);
         } else if (this.is_valid_cell_index(index)) {
             // otherwise always somewhere to append to
             this.get_cell_element(index).before(element);
         } else {
             return false;
         }
 
         if (this.undelete_index !== null && index <= this.undelete_index) {
             this.undelete_index = this.undelete_index + 1;
             this.set_dirty(true);
         }
         return true;
     };
 
     /**
      * Insert a cell of given type above given index, or at top
      * of notebook if index smaller than 0.
      *
      * default index value is the one of currently selected cell
      *
      * @method insert_cell_above
      * @param [type] {string} cell type
      * @param [index] {integer}
      *
      * @return handle to created cell or null
      **/
     Notebook.prototype.insert_cell_above = function (type, index) {
         index = this.index_or_selected(index);
         return this.insert_cell_at_index(type, index);
     };
 
     /**
      * Insert a cell of given type below given index, or at bottom
      * of notebook if index greater than number of cells
      *
      * default index value is the one of currently selected cell
      *
      * @method insert_cell_below
      * @param [type] {string} cell type
      * @param [index] {integer}
      *
      * @return handle to created cell or null
      *
      **/
     Notebook.prototype.insert_cell_below = function (type, index) {
         index = this.index_or_selected(index);
         return this.insert_cell_at_index(type, index+1);
     };
 
 
     /**
      * Insert cell at end of notebook
      *
      * @method insert_cell_at_bottom
      * @param {String} type cell type
      *
      * @return the added cell; or null
      **/
     Notebook.prototype.insert_cell_at_bottom = function (type){
         var len = this.ncells();
         return this.insert_cell_below(type,len-1);
     };
 
     /**
      * Turn a cell into a code cell.
      * 
      * @method to_code
      * @param {Number} [index] A cell's index
      */
     Notebook.prototype.to_code = function (index) {
         var i = this.index_or_selected(index);
         if (this.is_valid_cell_index(i)) {
             var source_cell = this.get_cell(i);
             if (!(source_cell instanceof codecell.CodeCell)) {
                 var target_cell = this.insert_cell_below('code',i);
                 var text = source_cell.get_text();
                 if (text === source_cell.placeholder) {
                     text = '';
                 }
                 //metadata
                 target_cell.metadata = source_cell.metadata;
 
                 target_cell.set_text(text);
                 // make this value the starting point, so that we can only undo
                 // to this state, instead of a blank cell
                 target_cell.code_mirror.clearHistory();
                 source_cell.element.remove();
                 this.select(i);
                 var cursor = source_cell.code_mirror.getCursor();
                 target_cell.code_mirror.setCursor(cursor);
                 this.set_dirty(true);
             }
         }
     };
 
     /**
      * Turn a cell into a Markdown cell.
      * 
      * @method to_markdown
      * @param {Number} [index] A cell's index
      */
     Notebook.prototype.to_markdown = function (index) {
         var i = this.index_or_selected(index);
         if (this.is_valid_cell_index(i)) {
             var source_cell = this.get_cell(i);
 
             if (!(source_cell instanceof textcell.MarkdownCell)) {
                 var target_cell = this.insert_cell_below('markdown',i);
                 var text = source_cell.get_text();
 
                 if (text === source_cell.placeholder) {
                     text = '';
                 }
                 // metadata
                 target_cell.metadata = source_cell.metadata;
                 // We must show the editor before setting its contents
                 target_cell.unrender();
                 target_cell.set_text(text);
                 // make this value the starting point, so that we can only undo
                 // to this state, instead of a blank cell
                 target_cell.code_mirror.clearHistory();
                 source_cell.element.remove();
                 this.select(i);
                 if ((source_cell instanceof textcell.TextCell) && source_cell.rendered) {
                     target_cell.render();
                 }
                 var cursor = source_cell.code_mirror.getCursor();
                 target_cell.code_mirror.setCursor(cursor);
                 this.set_dirty(true);
             }
         }
     };
 
     /**
      * Turn a cell into a raw text cell.
      * 
      * @method to_raw
      * @param {Number} [index] A cell's index
      */
     Notebook.prototype.to_raw = function (index) {
         var i = this.index_or_selected(index);
         if (this.is_valid_cell_index(i)) {
             var target_cell = null;
             var source_cell = this.get_cell(i);
 
             if (!(source_cell instanceof textcell.RawCell)) {
                 target_cell = this.insert_cell_below('raw',i);
                 var text = source_cell.get_text();
                 if (text === source_cell.placeholder) {
                     text = '';
                 }
                 //metadata
                 target_cell.metadata = source_cell.metadata;
                 // We must show the editor before setting its contents
                 target_cell.unrender();
                 target_cell.set_text(text);
                 // make this value the starting point, so that we can only undo
                 // to this state, instead of a blank cell
                 target_cell.code_mirror.clearHistory();
                 source_cell.element.remove();
                 this.select(i);
                 var cursor = source_cell.code_mirror.getCursor();
                 target_cell.code_mirror.setCursor(cursor);
                 this.set_dirty(true);
             }
         }
     };
     
     Notebook.prototype._warn_heading = function () {
         /**
          * warn about heading cells being removed
          */
         dialog.modal({
             notebook: this,
             keyboard_manager: this.keyboard_manager,
             title : "Use markdown headings",
             body : $("<p/>").text(
                 'IPython no longer uses special heading cells. ' + 
                 'Instead, write your headings in Markdown cells using # characters:'
             ).append($('<pre/>').text(
                 '## This is a level 2 heading'
             )),
             buttons : {
                 "OK" : {}
             }
         });
     };
     
     /**
      * Turn a cell into a markdown cell with a heading.
      * 
      * @method to_heading
      * @param {Number} [index] A cell's index
      * @param {Number} [level] A heading level (e.g., 1 for h1)
      */
     Notebook.prototype.to_heading = function (index, level) {
         this.to_markdown(index);
         level = level || 1;
         var i = this.index_or_selected(index);
         if (this.is_valid_cell_index(i)) {
             var cell = this.get_cell(i);
             cell.set_heading_level(level);
             this.set_dirty(true);
         }
     };
 
 
     // Cut/Copy/Paste
 
     /**
      * Enable UI elements for pasting cells.
      * 
      * @method enable_paste
      */
     Notebook.prototype.enable_paste = function () {
         var that = this;
         if (!this.paste_enabled) {
             $('#paste_cell_replace').removeClass('disabled')
                 .on('click', function () {that.paste_cell_replace();});
             $('#paste_cell_above').removeClass('disabled')
                 .on('click', function () {that.paste_cell_above();});
             $('#paste_cell_below').removeClass('disabled')
                 .on('click', function () {that.paste_cell_below();});
             this.paste_enabled = true;
         }
     };
 
     /**
      * Disable UI elements for pasting cells.
      * 
      * @method disable_paste
      */
     Notebook.prototype.disable_paste = function () {
         if (this.paste_enabled) {
             $('#paste_cell_replace').addClass('disabled').off('click');
             $('#paste_cell_above').addClass('disabled').off('click');
             $('#paste_cell_below').addClass('disabled').off('click');
             this.paste_enabled = false;
         }
     };
 
     /**
      * Cut a cell.
      * 
      * @method cut_cell
      */
     Notebook.prototype.cut_cell = function () {
         this.copy_cell();
         this.delete_cell();
     };
 
     /**
      * Copy a cell.
      * 
      * @method copy_cell
      */
     Notebook.prototype.copy_cell = function () {
         var cell = this.get_selected_cell();
         this.clipboard = cell.toJSON();
         // remove undeletable status from the copied cell
         if (this.clipboard.metadata.deletable !== undefined) {
             delete this.clipboard.metadata.deletable;
         }
         this.enable_paste();
     };
 
     /**
      * Replace the selected cell with a cell in the clipboard.
      * 
      * @method paste_cell_replace
      */
     Notebook.prototype.paste_cell_replace = function () {
         if (this.clipboard !== null && this.paste_enabled) {
             var cell_data = this.clipboard;
             var new_cell = this.insert_cell_above(cell_data.cell_type);
             new_cell.fromJSON(cell_data);
             var old_cell = this.get_next_cell(new_cell);
             this.delete_cell(this.find_cell_index(old_cell));
             this.select(this.find_cell_index(new_cell));
         }
     };
 
     /**
      * Paste a cell from the clipboard above the selected cell.
      * 
      * @method paste_cell_above
      */
     Notebook.prototype.paste_cell_above = function () {
         if (this.clipboard !== null && this.paste_enabled) {
             var cell_data = this.clipboard;
             var new_cell = this.insert_cell_above(cell_data.cell_type);
             new_cell.fromJSON(cell_data);
             new_cell.focus_cell();
         }
     };
 
     /**
      * Paste a cell from the clipboard below the selected cell.
      * 
      * @method paste_cell_below
      */
     Notebook.prototype.paste_cell_below = function () {
         if (this.clipboard !== null && this.paste_enabled) {
             var cell_data = this.clipboard;
             var new_cell = this.insert_cell_below(cell_data.cell_type);
             new_cell.fromJSON(cell_data);
             new_cell.focus_cell();
         }
     };
 
     // Split/merge
 
     /**
      * Split the selected cell into two, at the cursor.
      * 
      * @method split_cell
      */
     Notebook.prototype.split_cell = function () {
         var cell = this.get_selected_cell();
         if (cell.is_splittable()) {
             var texta = cell.get_pre_cursor();
             var textb = cell.get_post_cursor();
             cell.set_text(textb);
             var new_cell = this.insert_cell_above(cell.cell_type);
             // Unrender the new cell so we can call set_text.
             new_cell.unrender();
             new_cell.set_text(texta);
         }
     };
 
     /**
      * Combine the selected cell into the cell above it.
      * 
      * @method merge_cell_above
      */
     Notebook.prototype.merge_cell_above = function () {
         var index = this.get_selected_index();
         var cell = this.get_cell(index);
         var render = cell.rendered;
         if (!cell.is_mergeable()) {
             return;
         }
         if (index > 0) {
             var upper_cell = this.get_cell(index-1);
             if (!upper_cell.is_mergeable()) {
                 return;
             }
             var upper_text = upper_cell.get_text();
             var text = cell.get_text();
             if (cell instanceof codecell.CodeCell) {
                 cell.set_text(upper_text+'\n'+text);
             } else {
                 cell.unrender(); // Must unrender before we set_text.
                 cell.set_text(upper_text+'\n\n'+text);
                 if (render) {
                     // The rendered state of the final cell should match
                     // that of the original selected cell;
                     cell.render();
                 }
             }
             this.delete_cell(index-1);
             this.select(this.find_cell_index(cell));
         }
     };
 
     /**
      * Combine the selected cell into the cell below it.
      * 
      * @method merge_cell_below
      */
     Notebook.prototype.merge_cell_below = function () {
         var index = this.get_selected_index();
         var cell = this.get_cell(index);
         var render = cell.rendered;
         if (!cell.is_mergeable()) {
             return;
         }
         if (index < this.ncells()-1) {
             var lower_cell = this.get_cell(index+1);
             if (!lower_cell.is_mergeable()) {
                 return;
             }
             var lower_text = lower_cell.get_text();
             var text = cell.get_text();
             if (cell instanceof codecell.CodeCell) {
                 cell.set_text(text+'\n'+lower_text);
             } else {
                 cell.unrender(); // Must unrender before we set_text.
                 cell.set_text(text+'\n\n'+lower_text);
                 if (render) {
                     // The rendered state of the final cell should match
                     // that of the original selected cell;
                     cell.render();
                 }
             }
             this.delete_cell(index+1);
             this.select(this.find_cell_index(cell));
         }
     };
 
 
     // Cell collapsing and output clearing
 
     /**
      * Hide a cell's output.
      * 
      * @method collapse_output
      * @param {Number} index A cell's numeric index
      */
     Notebook.prototype.collapse_output = function (index) {
         var i = this.index_or_selected(index);
         var cell = this.get_cell(i);
         if (cell !== null && (cell instanceof codecell.CodeCell)) {
             cell.collapse_output();
             this.set_dirty(true);
         }
     };
 
     /**
      * Hide each code cell's output area.
      * 
      * @method collapse_all_output
      */
     Notebook.prototype.collapse_all_output = function () {
         this.get_cells().map(function (cell, i) {
             if (cell instanceof codecell.CodeCell) {
                 cell.collapse_output();
             }
         });
         // this should not be set if the `collapse` key is removed from nbformat
         this.set_dirty(true);
     };
 
     /**
      * Show a cell's output.
      * 
      * @method expand_output
      * @param {Number} index A cell's numeric index
      */
     Notebook.prototype.expand_output = function (index) {
         var i = this.index_or_selected(index);
         var cell = this.get_cell(i);
         if (cell !== null && (cell instanceof codecell.CodeCell)) {
             cell.expand_output();
             this.set_dirty(true);
         }
     };
 
     /**
      * Expand each code cell's output area, and remove scrollbars.
      * 
      * @method expand_all_output
      */
     Notebook.prototype.expand_all_output = function () {
         this.get_cells().map(function (cell, i) {
             if (cell instanceof codecell.CodeCell) {
                 cell.expand_output();
             }
         });
         // this should not be set if the `collapse` key is removed from nbformat
         this.set_dirty(true);
     };
 
     /**
      * Clear the selected CodeCell's output area.
      * 
      * @method clear_output
      * @param {Number} index A cell's numeric index
      */
     Notebook.prototype.clear_output = function (index) {
         var i = this.index_or_selected(index);
         var cell = this.get_cell(i);
         if (cell !== null && (cell instanceof codecell.CodeCell)) {
             cell.clear_output();
             this.set_dirty(true);
         }
     };
 
     /**
      * Clear each code cell's output area.
      * 
      * @method clear_all_output
      */
     Notebook.prototype.clear_all_output = function () {
         this.get_cells().map(function (cell, i) {
             if (cell instanceof codecell.CodeCell) {
                 cell.clear_output();
             }
         });
         this.set_dirty(true);
     };
 
     /**
      * Scroll the selected CodeCell's output area.
      * 
      * @method scroll_output
      * @param {Number} index A cell's numeric index
      */
     Notebook.prototype.scroll_output = function (index) {
         var i = this.index_or_selected(index);
         var cell = this.get_cell(i);
         if (cell !== null && (cell instanceof codecell.CodeCell)) {
             cell.scroll_output();
             this.set_dirty(true);
         }
     };
 
     /**
      * Expand each code cell's output area, and add a scrollbar for long output.
      * 
      * @method scroll_all_output
      */
     Notebook.prototype.scroll_all_output = function () {
         this.get_cells().map(function (cell, i) {
             if (cell instanceof codecell.CodeCell) {
                 cell.scroll_output();
             }
         });
         // this should not be set if the `collapse` key is removed from nbformat
         this.set_dirty(true);
     };
 
     /** Toggle whether a cell's output is collapsed or expanded.
      * 
      * @method toggle_output
      * @param {Number} index A cell's numeric index
      */
     Notebook.prototype.toggle_output = function (index) {
         var i = this.index_or_selected(index);
         var cell = this.get_cell(i);
         if (cell !== null && (cell instanceof codecell.CodeCell)) {
             cell.toggle_output();
             this.set_dirty(true);
         }
     };
 
     /**
      * Hide/show the output of all cells.
      * 
      * @method toggle_all_output
      */
     Notebook.prototype.toggle_all_output = function () {
         this.get_cells().map(function (cell, i) {
             if (cell instanceof codecell.CodeCell) {
                 cell.toggle_output();
             }
         });
         // this should not be set if the `collapse` key is removed from nbformat
         this.set_dirty(true);
     };
 
     /**
      * Toggle a scrollbar for long cell outputs.
      * 
      * @method toggle_output_scroll
      * @param {Number} index A cell's numeric index
      */
     Notebook.prototype.toggle_output_scroll = function (index) {
         var i = this.index_or_selected(index);
         var cell = this.get_cell(i);
         if (cell !== null && (cell instanceof codecell.CodeCell)) {
             cell.toggle_output_scroll();
             this.set_dirty(true);
         }
     };
 
     /**
      * Toggle the scrolling of long output on all cells.
      * 
      * @method toggle_all_output_scrolling
      */
     Notebook.prototype.toggle_all_output_scroll = function () {
         this.get_cells().map(function (cell, i) {
             if (cell instanceof codecell.CodeCell) {
                 cell.toggle_output_scroll();
             }
         });
         // this should not be set if the `collapse` key is removed from nbformat
         this.set_dirty(true);
     };
 
     // Other cell functions: line numbers, ...
 
     /**
      * Toggle line numbers in the selected cell's input area.
      * 
      * @method cell_toggle_line_numbers
      */
     Notebook.prototype.cell_toggle_line_numbers = function() {
         this.get_selected_cell().toggle_line_numbers();
     };
     
     /**
      * Set the codemirror mode for all code cells, including the default for
      * new code cells.
      * 
      * @method set_codemirror_mode
      */
     Notebook.prototype.set_codemirror_mode = function(newmode){
         if (newmode === this.codemirror_mode) {
             return;
         }
         this.codemirror_mode = newmode;
         codecell.CodeCell.options_default.cm_config.mode = newmode;
-        var modename = newmode.mode || newmode.name || newmode;
         
         var that = this;
-        utils.requireCodeMirrorMode(modename, function () {
+        utils.requireCodeMirrorMode(newmode, function () {
             that.get_cells().map(function(cell, i) {
                 if (cell.cell_type === 'code'){
                     cell.code_mirror.setOption('mode', newmode);
                     // This is currently redundant, because cm_config ends up as
                     // codemirror's own .options object, but I don't want to
                     // rely on that.
                     cell.cm_config.mode = newmode;
                 }
             });
         });
     };
 
     // Session related things
 
     /**
      * Start a new session and set it on each code cell.
      * 
      * @method start_session
      */
     Notebook.prototype.start_session = function (kernel_name) {
         if (this._session_starting) {
             throw new session.SessionAlreadyStarting();
         }
         this._session_starting = true;
 
         var options = {
             base_url: this.base_url,
             ws_url: this.ws_url,
             notebook_path: this.notebook_path,
             notebook_name: this.notebook_name,
             kernel_name: kernel_name,
             notebook: this
         };
 
         var success = $.proxy(this._session_started, this);
         var failure = $.proxy(this._session_start_failed, this);
 
         if (this.session !== null) {
             this.session.restart(options, success, failure);
         } else {
             this.session = new session.Session(options);
             this.session.start(success, failure);
         }
     };
 
 
     /**
      * Once a session is started, link the code cells to the kernel and pass the 
      * comm manager to the widget manager
      *
      */
     Notebook.prototype._session_started = function (){
         this._session_starting = false;
         this.kernel = this.session.kernel;
         var ncells = this.ncells();
         for (var i=0; i<ncells; i++) {
             var cell = this.get_cell(i);
             if (cell instanceof codecell.CodeCell) {
                 cell.set_kernel(this.session.kernel);
             }
         }
     };
     Notebook.prototype._session_start_failed = function (jqxhr, status, error){
         this._session_starting = false;
         utils.log_ajax_error(jqxhr, status, error);
     };
     
     /**
      * Prompt the user to restart the IPython kernel.
      * 
      * @method restart_kernel
      */
     Notebook.prototype.restart_kernel = function () {
         var that = this;
         dialog.modal({
             notebook: this,
             keyboard_manager: this.keyboard_manager,
             title : "Restart kernel or continue running?",
             body : $("<p/>").text(
                 'Do you want to restart the current kernel?  You will lose all variables defined in it.'
             ),
             buttons : {
                 "Continue running" : {},
                 "Restart" : {
                     "class" : "btn-danger",
                     "click" : function() {
                         that.kernel.restart();
                     }
                 }
             }
         });
     };
     
     /**
      * Execute or render cell outputs and go into command mode.
      * 
      * @method execute_cell
      */
     Notebook.prototype.execute_cell = function () {
         /**
          * mode = shift, ctrl, alt
          */
         var cell = this.get_selected_cell();
         
         cell.execute();
         this.command_mode();
         this.set_dirty(true);
     };
 
     /**
      * Execute or render cell outputs and insert a new cell below.
      * 
      * @method execute_cell_and_insert_below
      */
     Notebook.prototype.execute_cell_and_insert_below = function () {
         var cell = this.get_selected_cell();
         var cell_index = this.find_cell_index(cell);
         
         cell.execute();
 
         // If we are at the end always insert a new cell and return
         if (cell_index === (this.ncells()-1)) {
             this.command_mode();
             this.insert_cell_below();
             this.select(cell_index+1);
             this.edit_mode();
             this.scroll_to_bottom();
             this.set_dirty(true);
             return;
         }
 
         this.command_mode();
         this.insert_cell_below();
         this.select(cell_index+1);
         this.edit_mode();
         this.set_dirty(true);
     };
 
     /**
      * Execute or render cell outputs and select the next cell.
      * 
      * @method execute_cell_and_select_below
      */
     Notebook.prototype.execute_cell_and_select_below = function () {
 
         var cell = this.get_selected_cell();
         var cell_index = this.find_cell_index(cell);
         
         cell.execute();
 
         // If we are at the end always insert a new cell and return
         if (cell_index === (this.ncells()-1)) {
             this.command_mode();
             this.insert_cell_below();
             this.select(cell_index+1);
             this.edit_mode();
             this.scroll_to_bottom();
             this.set_dirty(true);
             return;
         }
 
         this.command_mode();
         this.select(cell_index+1);
         this.focus_cell();
         this.set_dirty(true);
     };
 
     /**
      * Execute all cells below the selected cell.
      * 
      * @method execute_cells_below
      */
     Notebook.prototype.execute_cells_below = function () {
         this.execute_cell_range(this.get_selected_index(), this.ncells());
         this.scroll_to_bottom();
     };
 
     /**
      * Execute all cells above the selected cell.
      * 
      * @method execute_cells_above
      */
     Notebook.prototype.execute_cells_above = function () {
         this.execute_cell_range(0, this.get_selected_index());
     };
 
     /**
      * Execute all cells.
      * 
      * @method execute_all_cells
      */
     Notebook.prototype.execute_all_cells = function () {
         this.execute_cell_range(0, this.ncells());
         this.scroll_to_bottom();
     };
 
     /**
      * Execute a contiguous range of cells.
      * 
      * @method execute_cell_range
      * @param {Number} start Index of the first cell to execute (inclusive)
      * @param {Number} end Index of the last cell to execute (exclusive)
      */
     Notebook.prototype.execute_cell_range = function (start, end) {
         this.command_mode();
         for (var i=start; i<end; i++) {
             this.select(i);
             this.execute_cell();
         }
     };
 
     // Persistance and loading
 
     /**
      * Getter method for this notebook's name.
      * 
      * @method get_notebook_name
      * @return {String} This notebook's name (excluding file extension)
      */
     Notebook.prototype.get_notebook_name = function () {
         var nbname = this.notebook_name.substring(0,this.notebook_name.length-6);
         return nbname;
     };
 
     /**
      * Setter method for this notebook's name.
      *
      * @method set_notebook_name
      * @param {String} name A new name for this notebook
      */
     Notebook.prototype.set_notebook_name = function (name) {
         var parent = utils.url_path_split(this.notebook_path)[0];
         this.notebook_name = name;
         this.notebook_path = utils.url_path_join(parent, name);
     };
 
     /**
      * Check that a notebook's name is valid.
      * 
      * @method test_notebook_name
      * @param {String} nbname A name for this notebook
      * @return {Boolean} True if the name is valid, false if invalid
      */
     Notebook.prototype.test_notebook_name = function (nbname) {
         nbname = nbname || '';
         if (nbname.length>0 && !this.notebook_name_blacklist_re.test(nbname)) {
             return true;
         } else {
             return false;
         }
     };
 
     /**
      * Load a notebook from JSON (.ipynb).
      * 
      * @method fromJSON
      * @param {Object} data JSON representation of a notebook
      */
     Notebook.prototype.fromJSON = function (data) {
 
         var content = data.content;
         var ncells = this.ncells();
         var i;
         for (i=0; i<ncells; i++) {
             // Always delete cell 0 as they get renumbered as they are deleted.
             this.delete_cell(0);
         }
         // Save the metadata and name.
         this.metadata = content.metadata;
         this.notebook_name = data.name;
         this.notebook_path = data.path;
         var trusted = true;
         
         // Trigger an event changing the kernel spec - this will set the default
         // codemirror mode
         if (this.metadata.kernelspec !== undefined) {
             this.events.trigger('spec_changed.Kernel', this.metadata.kernelspec);
         }
         
         // Set the codemirror mode from language_info metadata
         if (this.metadata.language_info !== undefined) {
             var langinfo = this.metadata.language_info;
             // Mode 'null' should be plain, unhighlighted text.
             var cm_mode = langinfo.codemirror_mode || langinfo.name || 'null';
             this.set_codemirror_mode(cm_mode);
         }
         
         var new_cells = content.cells;
         ncells = new_cells.length;
         var cell_data = null;
         var new_cell = null;
         for (i=0; i<ncells; i++) {
             cell_data = new_cells[i];
             new_cell = this.insert_cell_at_index(cell_data.cell_type, i);
             new_cell.fromJSON(cell_data);
             if (new_cell.cell_type == 'code' && !new_cell.output_area.trusted) {
                 trusted = false;
             }
         }
         if (trusted !== this.trusted) {
             this.trusted = trusted;
             this.events.trigger("trust_changed.Notebook", trusted);
         }
     };
 
     /**
      * Dump this notebook into a JSON-friendly object.
      * 
      * @method toJSON
      * @return {Object} A JSON-friendly representation of this notebook.
      */
     Notebook.prototype.toJSON = function () {
         /**
          * remove the conversion indicator, which only belongs in-memory
          */
         delete this.metadata.orig_nbformat;
         delete this.metadata.orig_nbformat_minor;
 
         var cells = this.get_cells();
         var ncells = cells.length;
         var cell_array = new Array(ncells);
         var trusted = true;
         for (var i=0; i<ncells; i++) {
             var cell = cells[i];
             if (cell.cell_type == 'code' && !cell.output_area.trusted) {
                 trusted = false;
             }
             cell_array[i] = cell.toJSON();
         }
         var data = {
             cells: cell_array,
             metadata: this.metadata,
             nbformat: this.nbformat,
             nbformat_minor: this.nbformat_minor
         };
         if (trusted != this.trusted) {
             this.trusted = trusted;
             this.events.trigger("trust_changed.Notebook", trusted);
         }
         return data;
     };
 
     /**
      * Start an autosave timer, for periodically saving the notebook.
      * 
      * @method set_autosave_interval
      * @param {Integer} interval the autosave interval in milliseconds
      */
     Notebook.prototype.set_autosave_interval = function (interval) {
         var that = this;
         // clear previous interval, so we don't get simultaneous timers
         if (this.autosave_timer) {
             clearInterval(this.autosave_timer);
         }
         if (!this.writable) {
             // disable autosave if not writable
             interval = 0;
         }
         
         this.autosave_interval = this.minimum_autosave_interval = interval;
         if (interval) {
             this.autosave_timer = setInterval(function() {
                 if (that.dirty) {
                     that.save_notebook();
                 }
             }, interval);
             this.events.trigger("autosave_enabled.Notebook", interval);
         } else {
             this.autosave_timer = null;
             this.events.trigger("autosave_disabled.Notebook");
         }
     };
     
     /**
      * Save this notebook on the server. This becomes a notebook instance's
      * .save_notebook method *after* the entire notebook has been loaded.
      * 
      * @method save_notebook
      */
     Notebook.prototype.save_notebook = function () {
         if (!this._fully_loaded) {
             this.events.trigger('notebook_save_failed.Notebook',
                 new Error("Load failed, save is disabled")
             );
             return;
         } else if (!this.writable) {
             this.events.trigger('notebook_save_failed.Notebook',
                 new Error("Notebook is read-only")
             );
             return;
         }
 
         // Create a JSON model to be sent to the server.
         var model = {
             type : "notebook",
             content : this.toJSON()
         };
         // time the ajax call for autosave tuning purposes.
         var start =  new Date().getTime();
 
         var that = this;
         return this.contents.save(this.notebook_path, model).then(
                 $.proxy(this.save_notebook_success, this, start),
                 function (error) {
                     that.events.trigger('notebook_save_failed.Notebook', error);
                 }
             );
     };
     
     /**
      * Success callback for saving a notebook.
      * 
      * @method save_notebook_success
      * @param {Integer} start Time when the save request start
      * @param {Object} data JSON representation of a notebook
      */
     Notebook.prototype.save_notebook_success = function (start, data) {
         this.set_dirty(false);
         if (data.message) {
             // save succeeded, but validation failed.
             var body = $("<div>");
             var title = "Notebook validation failed";
 
             body.append($("<p>").text(
                 "The save operation succeeded," +
                 " but the notebook does not appear to be valid." +
                 " The validation error was:"
             )).append($("<div>").addClass("validation-error").append(
                 $("<pre>").text(data.message)
             ));
             dialog.modal({
                 notebook: this,
                 keyboard_manager: this.keyboard_manager,
                 title: title,
                 body: body,
                 buttons : {
                     OK : {
                         "class" : "btn-primary"
                     }
                 }
             });
         }
         this.events.trigger('notebook_saved.Notebook');
         this._update_autosave_interval(start);
         if (this._checkpoint_after_save) {
             this.create_checkpoint();
             this._checkpoint_after_save = false;
         }
     };
     
     /**
      * update the autosave interval based on how long the last save took
      * 
      * @method _update_autosave_interval
      * @param {Integer} timestamp when the save request started
      */
     Notebook.prototype._update_autosave_interval = function (start) {
         var duration = (new Date().getTime() - start);
         if (this.autosave_interval) {
             // new save interval: higher of 10x save duration or parameter (default 30 seconds)
             var interval = Math.max(10 * duration, this.minimum_autosave_interval);
             // round to 10 seconds, otherwise we will be setting a new interval too often
             interval = 10000 * Math.round(interval / 10000);
             // set new interval, if it's changed
             if (interval != this.autosave_interval) {
                 this.set_autosave_interval(interval);
             }
         }
     };
 
     /**
      * Explicitly trust the output of this notebook.
      *
      * @method trust_notebook
      */
     Notebook.prototype.trust_notebook = function () {
         var body = $("<div>").append($("<p>")
             .text("A trusted IPython notebook may execute hidden malicious code ")
             .append($("<strong>")
                 .append(
                     $("<em>").text("when you open it")
                 )
             ).append(".").append(
                 " Selecting trust will immediately reload this notebook in a trusted state."
             ).append(
                 " For more information, see the "
             ).append($("<a>").attr("href", "http://ipython.org/ipython-doc/2/notebook/security.html")
                 .text("IPython security documentation")
             ).append(".")
         );
 
         var nb = this;
         dialog.modal({
             notebook: this,
             keyboard_manager: this.keyboard_manager,
             title: "Trust this notebook?",
             body: body,
 
             buttons: {
                 Cancel : {},
                 Trust : {
                     class : "btn-danger",
                     click : function () {
                         var cells = nb.get_cells();
                         for (var i = 0; i < cells.length; i++) {
                             var cell = cells[i];
                             if (cell.cell_type == 'code') {
                                 cell.output_area.trusted = true;
                             }
                         }
                         nb.events.on('notebook_saved.Notebook', function () {
                             window.location.reload();
                         });
                         nb.save_notebook();
                     }
                 }
             }
         });
     };
 
     Notebook.prototype.copy_notebook = function () {
         var that = this;
         var base_url = this.base_url;
         var w = window.open();
         var parent = utils.url_path_split(this.notebook_path)[0];
         this.contents.copy(this.notebook_path, parent).then(
             function (data) {
                 w.location = utils.url_join_encode(
                     base_url, 'notebooks', data.path
                 );
             },
             function(error) {
                 w.close();
                 that.events.trigger('notebook_copy_failed', error);
             }
         );
     };
 
     Notebook.prototype.rename = function (new_name) {
         if (!new_name.match(/\.ipynb$/)) {
             new_name = new_name + ".ipynb";
         }
 
         var that = this;
         var parent = utils.url_path_split(this.notebook_path)[0];
         var new_path = utils.url_path_join(parent, new_name);
         return this.contents.rename(this.notebook_path, new_path).then(
             function (json) {
                 that.notebook_name = json.name;
                 that.notebook_path = json.path;
                 that.session.rename_notebook(json.path);
                 that.events.trigger('notebook_renamed.Notebook', json);
             }
         );
     };
 
     Notebook.prototype.delete = function () {
         this.contents.delete(this.notebook_path);
     };
 
     /**
      * Request a notebook's data from the server.
      * 
      * @method load_notebook
      * @param {String} notebook_path A notebook to load
      */
     Notebook.prototype.load_notebook = function (notebook_path) {
         this.notebook_path = notebook_path;
         this.notebook_name = utils.url_path_split(this.notebook_path)[1];
         this.events.trigger('notebook_loading.Notebook');
         this.contents.get(notebook_path, {type: 'notebook'}).then(
             $.proxy(this.load_notebook_success, this),
             $.proxy(this.load_notebook_error, this)
         );
     };
 
     /**
      * Success callback for loading a notebook from the server.
      * 
      * Load notebook data from the JSON response.
      * 
      * @method load_notebook_success
      * @param {Object} data JSON representation of a notebook
      */
     Notebook.prototype.load_notebook_success = function (data) {
         var failed, msg;
         try {
             this.fromJSON(data);
         } catch (e) {
             failed = e;
             console.log("Notebook failed to load from JSON:", e);
         }
         if (failed || data.message) {
             // *either* fromJSON failed or validation failed
             var body = $("<div>");
             var title;
             if (failed) {
                 title = "Notebook failed to load";
                 body.append($("<p>").text(
                     "The error was: "
                 )).append($("<div>").addClass("js-error").text(
                     failed.toString()
                 )).append($("<p>").text(
                     "See the error console for details."
                 ));
             } else {
                 title = "Notebook validation failed";
             }
 
             if (data.message) {
                 if (failed) {
                     msg = "The notebook also failed validation:";
                 } else {
                     msg = "An invalid notebook may not function properly." +
                     " The validation error was:";
                 }
                 body.append($("<p>").text(
                     msg
                 )).append($("<div>").addClass("validation-error").append(
                     $("<pre>").text(data.message)
                 ));
             }
 
             dialog.modal({
                 notebook: this,
                 keyboard_manager: this.keyboard_manager,
                 title: title,
                 body: body,
                 buttons : {
                     OK : {
                         "class" : "btn-primary"
                     }
                 }
             });
         }
         if (this.ncells() === 0) {
             this.insert_cell_below('code');
             this.edit_mode(0);
         } else {
             this.select(0);
             this.handle_command_mode(this.get_cell(0));
         }
         this.set_dirty(false);
         this.scroll_to_top();
         this.writable = data.writable || false;
         var nbmodel = data.content;
         var orig_nbformat = nbmodel.metadata.orig_nbformat;
         var orig_nbformat_minor = nbmodel.metadata.orig_nbformat_minor;
         if (orig_nbformat !== undefined && nbmodel.nbformat !== orig_nbformat) {
             var src;
             if (nbmodel.nbformat > orig_nbformat) {
                 src = " an older notebook format ";
             } else {
                 src = " a newer notebook format ";
             }
             
             msg = "This notebook has been converted from" + src +
             "(v"+orig_nbformat+") to the current notebook " +
             "format (v"+nbmodel.nbformat+"). The next time you save this notebook, the " +
             "current notebook format will be used.";
             
             if (nbmodel.nbformat > orig_nbformat) {
                 msg += " Older versions of IPython may not be able to read the new format.";
             } else {
                 msg += " Some features of the original notebook may not be available.";
             }
             msg += " To preserve the original version, close the " +
                 "notebook without saving it.";
             dialog.modal({
                 notebook: this,
                 keyboard_manager: this.keyboard_manager,
                 title : "Notebook converted",
                 body : msg,
                 buttons : {
                     OK : {
                         class : "btn-primary"
                     }
                 }
             });
         } else if (this.nbformat_minor < nbmodel.nbformat_minor) {
             this.nbformat_minor = nbmodel.nbformat_minor;
         }
         
         // Create the session after the notebook is completely loaded to prevent
         // code execution upon loading, which is a security risk.
         if (this.session === null) {
             var kernel_name;
             if (this.metadata.kernelspec) {
                 var kernelspec = this.metadata.kernelspec || {};
                 kernel_name = kernelspec.name;
             } else {
                 kernel_name = utils.get_url_param('kernel_name');
             }
             this.start_session(kernel_name);
         }
         // load our checkpoint list
         this.list_checkpoints();
         
         // load toolbar state
         if (this.metadata.celltoolbar) {
             celltoolbar.CellToolbar.global_show();
             celltoolbar.CellToolbar.activate_preset(this.metadata.celltoolbar);
         } else {
             celltoolbar.CellToolbar.global_hide();
         }
         
         if (!this.writable) {
             this.set_autosave_interval(0);
             this.events.trigger('notebook_read_only.Notebook');
         }
         
         // now that we're fully loaded, it is safe to restore save functionality
         this._fully_loaded = true;
         this.events.trigger('notebook_loaded.Notebook');
     };
 
     /**
      * Failure callback for loading a notebook from the server.
      * 
      * @method load_notebook_error
      * @param {Error} error
      */
     Notebook.prototype.load_notebook_error = function (error) {
         this.events.trigger('notebook_load_failed.Notebook', error);
         var msg;
         if (error.name === utils.XHR_ERROR && error.xhr.status === 500) {
             utils.log_ajax_error(error.xhr, error.xhr_status, error.xhr_error);
             msg = "An unknown error occurred while loading this notebook. " +
             "This version can load notebook formats " +
             "v" + this.nbformat + " or earlier. See the server log for details.";
         } else {
             msg = error.message;
         }
         dialog.modal({
             notebook: this,
             keyboard_manager: this.keyboard_manager,
             title: "Error loading notebook",
             body : msg,
             buttons : {
                 "OK": {}
             }
         });
     };
 
     /*********************  checkpoint-related  *********************/
     
     /**
      * Save the notebook then immediately create a checkpoint.
      * 
      * @method save_checkpoint
      */
     Notebook.prototype.save_checkpoint = function () {
         this._checkpoint_after_save = true;
         this.save_notebook();
     };
     
     /**
      * Add a checkpoint for this notebook.
      * for use as a callback from checkpoint creation.
      * 
      * @method add_checkpoint
      */
     Notebook.prototype.add_checkpoint = function (checkpoint) {
         var found = false;
         for (var i = 0; i < this.checkpoints.length; i++) {
             var existing = this.checkpoints[i];
             if (existing.id == checkpoint.id) {
                 found = true;
                 this.checkpoints[i] = checkpoint;
                 break;
             }
         }
         if (!found) {
             this.checkpoints.push(checkpoint);
         }
         this.last_checkpoint = this.checkpoints[this.checkpoints.length - 1];
     };
     
     /**
      * List checkpoints for this notebook.
      * 
      * @method list_checkpoints
      */
     Notebook.prototype.list_checkpoints = function () {
         var that = this;
         this.contents.list_checkpoints(this.notebook_path).then(
             $.proxy(this.list_checkpoints_success, this),
             function(error) {
                 that.events.trigger('list_checkpoints_failed.Notebook', error);
             }
         );
     };
 
     /**
      * Success callback for listing checkpoints.
      * 
      * @method list_checkpoint_success
      * @param {Object} data JSON representation of a checkpoint
      */
     Notebook.prototype.list_checkpoints_success = function (data) {
         this.checkpoints = data;
         if (data.length) {
             this.last_checkpoint = data[data.length - 1];
         } else {
             this.last_checkpoint = null;
         }
         this.events.trigger('checkpoints_listed.Notebook', [data]);
     };
 
     /**
      * Create a checkpoint of this notebook on the server from the most recent save.
      * 
      * @method create_checkpoint
      */
     Notebook.prototype.create_checkpoint = function () {
         var that = this;
         this.contents.create_checkpoint(this.notebook_path).then(
             $.proxy(this.create_checkpoint_success, this),
             function (error) {
                 that.events.trigger('checkpoint_failed.Notebook', error);
             }
         );
     };
 
     /**
      * Success callback for creating a checkpoint.
      * 
      * @method create_checkpoint_success
      * @param {Object} data JSON representation of a checkpoint
      */
     Notebook.prototype.create_checkpoint_success = function (data) {
         this.add_checkpoint(data);
         this.events.trigger('checkpoint_created.Notebook', data);
     };
 
     Notebook.prototype.restore_checkpoint_dialog = function (checkpoint) {
         var that = this;
         checkpoint = checkpoint || this.last_checkpoint;
         if ( ! checkpoint ) {
             console.log("restore dialog, but no checkpoint to restore to!");
             return;
         }
         var body = $('<div/>').append(
             $('<p/>').addClass("p-space").text(
                 "Are you sure you want to revert the notebook to " +
                 "the latest checkpoint?"
             ).append(
                 $("<strong/>").text(
                     " This cannot be undone."
                 )
             )
         ).append(
             $('<p/>').addClass("p-space").text("The checkpoint was last updated at:")
         ).append(
             $('<p/>').addClass("p-space").text(
                 Date(checkpoint.last_modified)
             ).css("text-align", "center")
         );
         
         dialog.modal({
             notebook: this,
             keyboard_manager: this.keyboard_manager,
             title : "Revert notebook to checkpoint",
             body : body,
             buttons : {
                 Revert : {
                     class : "btn-danger",
                     click : function () {
                         that.restore_checkpoint(checkpoint.id);
                     }
                 },
                 Cancel : {}
                 }
         });
     };
     
     /**
      * Restore the notebook to a checkpoint state.
      * 
      * @method restore_checkpoint
      * @param {String} checkpoint ID
      */
     Notebook.prototype.restore_checkpoint = function (checkpoint) {
         this.events.trigger('notebook_restoring.Notebook', checkpoint);
         var that = this;
         this.contents.restore_checkpoint(this.notebook_path, checkpoint).then(
             $.proxy(this.restore_checkpoint_success, this),
             function (error) {
                 that.events.trigger('checkpoint_restore_failed.Notebook', error);
             }
         );
     };
     
     /**
      * Success callback for restoring a notebook to a checkpoint.
      * 
      * @method restore_checkpoint_success
      */
     Notebook.prototype.restore_checkpoint_success = function () {
         this.events.trigger('checkpoint_restored.Notebook');
         this.load_notebook(this.notebook_path);
     };
 
     /**
      * Delete a notebook checkpoint.
      * 
      * @method delete_checkpoint
      * @param {String} checkpoint ID
      */
     Notebook.prototype.delete_checkpoint = function (checkpoint) {
         this.events.trigger('notebook_restoring.Notebook', checkpoint);
         var that = this;
         this.contents.delete_checkpoint(this.notebook_path, checkpoint).then(
             $.proxy(this.delete_checkpoint_success, this),
             function (error) {
                 that.events.trigger('checkpoint_delete_failed.Notebook', error);
             }
         );
     };
     
     /**
      * Success callback for deleting a notebook checkpoint
      * 
      * @method delete_checkpoint_success
      */
     Notebook.prototype.delete_checkpoint_success = function () {
         this.events.trigger('checkpoint_deleted.Notebook');
         this.load_notebook(this.notebook_path);
     };
 
 
     // For backwards compatability.
     IPython.Notebook = Notebook;
 
     return {'Notebook': Notebook};
 });