various fixes in utils.js

revealed by linters

- remove duplicate WrappedError definition
- regex_split doesn't actually allow string separator
- remove various unused variables
- fix some incorrect regex escaping
- add missing quotes in $('body')
- remove a `for(attr in object)` because javascript

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

@@ -1,869 +1,829 b''
 // 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
+     * @param {RegExp} separator Regex 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
+        // Make `global` and avoid `lastIndex` issues by working with a copy
+        separator = new RegExp(separator.source, flags + "g");
 
         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)) {
+        for (match = separator.exec(str); match; 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());
+                var idx = parseInt(numbers.shift(), 10);
                 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];
+                Object.keys(attrs).map(function (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);
+        $('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);
+        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
          */
 
         var modename = (typeof mode == "string") ? mode :
             mode.mode || mode.name;
 
         // simplest, cheapest check by mode name: mode may also have config
         if (CodeMirror.modes.hasOwnProperty(modename)) {
             // return the full mode object, if it has a name
             callback(mode.name ? mode : modename);
             return;
         }
 
         // *somehow* get back a CM.modeInfo-like object that has .mode and
         // .mime
         var info = (mode && mode.mode && mode.mime && mode) ||
             CodeMirror.findModeByName(modename) ||
             CodeMirror.findModeByExtension(modename.split(".").slice(-1)) ||
             CodeMirror.findModeByMIME(modename) ||
             {mode: modename, mime: modename};
 
         require([
                 // might want to use CodeMirror.modeURL here
                 ['codemirror/mode', info.mode, info.mode].join('/'),
             ], function() {
               // return the original mode, as from a kernelspec on first load
               // or the mimetype, as for most highlighting
               callback(mode.name ? mode : 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;
 });