Hello strange new syntax. Can we be friends?

common/content/commandline.js

@@ -167,11 +167,11 @@ var CommandWidgets = Class("CommandWidgets", {
 
         function get(prefix, map, id) (obj.getElement || util.identity)(map[id] || document.getElementById(prefix + id));
 
-        this.active.__defineGetter__(obj.name, function () self.activeGroup[obj.name][obj.name]);
+        this.active.__defineGetter__(obj.name, () => this.activeGroup[obj.name][obj.name]);
-        this.activeGroup.__defineGetter__(obj.name, function () self.getGroup(obj.name));
+        this.activeGroup.__defineGetter__(obj.name, () => this.getGroup(obj.name));
 
-        memoize(this.statusbar, obj.name, function () get("dactyl-statusline-field-", statusline.widgets, (obj.id || obj.name)));
+        memoize(this.statusbar, obj.name, () => get("dactyl-statusline-field-", statusline.widgets, (obj.id || obj.name)));
-        memoize(this.commandbar, obj.name, function () get("dactyl-", {}, (obj.id || obj.name)));
+        memoize(this.commandbar, obj.name, () => get("dactyl-", {}, (obj.id || obj.name)));
 
         if (!(obj.noValue || obj.getValue)) {
             Object.defineProperty(this, obj.name, Modes.boundProperty({
@@ -504,8 +504,6 @@ var CommandPromptMode = Class("CommandPromptMode", CommandMode, {
  */
 var CommandLine = Module("commandline", {
     init: function init() {
-        const self = this;
-
         this._callbacks = {};
 
         memoize(this, "_store", function () storage.newMap("command-history", { store: true, privateData: true }));
@@ -777,13 +775,12 @@ var CommandLine = Module("commandline", {
 
         highlightGroup = highlightGroup || this.HL_NORMAL;
 
-        let self = this;
+        let appendToMessages = (data) => {
-        function appendToMessages(data) {
             let message = isObject(data) && !DOM.isJSONXML(data) ? data : { message: data };
 
             // Make sure the memoized message property is an instance property.
             message.message;
-            self._messageHistory.add(update({ highlight: highlightGroup }, message));
+            this._messageHistory.add(update({ highlight: highlightGroup }, message));
             return message.message;
         }
 
@@ -802,7 +799,7 @@ var CommandLine = Module("commandline", {
         if ((flags & this.FORCE_MULTILINE) || (/\n/.test(data) || !isinstance(data, [_, "String"])) && !(flags & this.FORCE_SINGLELINE))
             action = mow.closure.echo;
 
-        let checkSingleLine = function () action == self._echoLine;
+        let checkSingleLine = () => action == this._echoLine;
 
         if (forceSingle) {
             this._lastEcho = null;

common/content/dactyl.js

@@ -1,6 +1,6 @@
 // Copyright (c) 2006-2008 by Martin Stubenschrott <stubenschrott@vimperator.org>
 // Copyright (c) 2007-2011 by Doug Kearns <dougkearns@gmail.com>
-// Copyright (c) 2008-2012 Kris Maglione <maglione.k@gmail.com>
+// Copyright (c) 2008-2013 Kris Maglione <maglione.k@gmail.com>
 //
 // This work is licensed for reuse under an MIT license. Details are
 // given in the LICENSE.txt file included with this file.

common/content/key-processors.js

@@ -250,18 +250,17 @@ var KeyProcessor = Class("KeyProcessor", {
     },
 
     execute: function execute(map, args)
-        let (self = this)
+        () => {
-            function execute() {
+            if (this.preExecute)
-                if (self.preExecute)
+                this.preExecute.apply(this, args);
-                    self.preExecute.apply(self, args);
 
-                args.self = self.main.params.mappingSelf || self.main.mappingSelf || map;
+            args.self = this.main.params.mappingSelf || this.main.mappingSelf || map;
-                let res = map.execute.call(map, args);
+            let res = map.execute.call(map, args);
 
-                if (self.postExecute)
+            if (this.postExecute)
-                    self.postExecute.apply(self, args);
+                this.postExecute.apply(this, args);
-                return res;
+            return res;
-            },
+        },
 
     onKeyPress: function onKeyPress(event) {
         if (event.skipmap)

common/content/mappings.js

@@ -123,8 +123,7 @@ var Map = Class("Map", {
                                   contexts.context,
                                   args);
 
-        let self = this;
+        let repeat = () => this.action(args);
-        function repeat() self.action(args)
         if (this.names[0] != ".") // FIXME: Kludge.
             mappings.repeat = repeat;
 

common/modules/addons.jsm

@@ -211,9 +211,8 @@ var Addon = Class("Addon", {
     },
 
     update: function callee() {
-        let self = this;
+        let update = (key, xml) => {
-        function update(key, xml) {
+            let node = this.nodes[key];
-            let node = self.nodes[key];
             while (node.firstChild)
                 node.removeChild(node.firstChild);
 

common/modules/base.jsm

@@ -1,4 +1,4 @@
-// Copyright (c) 2009-2012 Kris Maglione <maglione.k@gmail.com>
+// Copyright (c) 2009-2013 Kris Maglione <maglione.k@gmail.com>
 //
 // This work is licensed for reuse under an MIT license. Details are
 // given in the LICENSE.txt file included with this file.
@@ -953,14 +953,13 @@ Class.prototype = {
      * @returns {nsITimer} The timer which backs this timeout.
      */
     timeout: function timeout(callback, timeout) {
-        const self = this;
+        let timeout_notify = (timer) => {
-        function timeout_notify(timer) {
+            if (this.stale ||
-            if (self.stale ||
                     util.rehashing && !isinstance(Cu.getGlobalForObject(callback), ["BackstagePass"]))
                 return;
-            self.timeouts.splice(self.timeouts.indexOf(timer), 1);
+            this.timeouts.splice(this.timeouts.indexOf(timer), 1);
-            util.trapErrors(callback, self);
+            util.trapErrors(callback, this);
-        }
+        };
         let timer = services.Timer(timeout_notify, timeout || 0, services.Timer.TYPE_ONE_SHOT);
         this.timeouts.push(timer);
         return timer;
@@ -973,12 +972,11 @@ Class.prototype = {
      * localized properties.
      */
     update: function update() {
-        let self = this;
         // XXX: Duplication.
 
         for (let i = 0; i < arguments.length; i++) {
             let src = arguments[i];
-            Object.getOwnPropertyNames(src || {}).forEach(function (k) {
+            Object.getOwnPropertyNames(src || {}).forEach((k) => {
                 let desc = Object.getOwnPropertyDescriptor(src, k);
                 if (desc.value instanceof Class.Property)
                     desc = desc.value.init(k, this) || desc.value;
@@ -986,12 +984,16 @@ Class.prototype = {
                 if (typeof desc.value === "function") {
                     let func = desc.value.wrapped || desc.value;
                     if (!func.superapply) {
-                        func.__defineGetter__("super", function () Object.getPrototypeOf(self)[k]);
+                        func.__defineGetter__("super", () => Object.getPrototypeOf(this)[k]);
-                        func.superapply = function superapply(self, args)
+
-                            let (meth = Object.getPrototypeOf(self)[k])
+                        func.superapply = function superapply(self, args) {
-                                meth && meth.apply(self, args);
+                            let meth = Object.getPrototypeOf(self)[k];
-                        func.supercall = function supercall(self)
+                            return meth && meth.apply(self, args);
-                            func.superapply(self, Array.slice(arguments, 1));
+                        };
+
+                        func.supercall = function supercall(self) {
+                            return func.superapply(self, Array.slice(arguments, 1));
+                        }
                     }
                 }
 

common/modules/buffer.jsm

@@ -995,8 +995,6 @@ var Buffer = Module("Buffer", {
     showPageInfo: function showPageInfo(verbose, sections) {
         let { commandline, dactyl, options } = this.modules;
 
-        let self = this;
-
         // Ctrl-g single line output
         if (!verbose) {
             let file = this.win.location.pathname.split("/").pop() || _("buffer.noName");
@@ -1004,7 +1002,7 @@ var Buffer = Module("Buffer", {
 
             let info = template.map(
                 (sections || options["pageinfo"])
-                    .map(function (opt) Buffer.pageInfo[opt].action.call(self)),
+                    .map((opt) => Buffer.pageInfo[opt].action.call(this)),
                 function (res) res && iter(res).join(", ") || undefined,
                 ", ").join("");
 
@@ -1016,9 +1014,9 @@ var Buffer = Module("Buffer", {
             return;
         }
 
-        let list = template.map(sections || options["pageinfo"], function (option) {
+        let list = template.map(sections || options["pageinfo"], (option) => {
             let { action, title } = Buffer.pageInfo[option];
-            return template.table(title, action.call(self, true));
+            return template.table(title, action.call(this, true));
         }, ["br"]);
 
         commandline.commandOutput(list);
@@ -1254,14 +1252,13 @@ var Buffer = Module("Buffer", {
      * Updates the zoom level of this buffer from a content preference.
      */
     updateZoom: util.wrapCallback(function updateZoom() {
-        let self = this;
         let uri = this.uri;
 
         if (prefs.get("browser.zoom.siteSpecific")) {
-            this.getPref("dactyl.content.full-zoom", function (val) {
+            this.getPref("dactyl.content.full-zoom", (val) => {
-                if (val != null && uri.equals(self.uri) && val != prefs.get("browser.zoom.full"))
+                if (val != null && uri.equals(this.uri) && val != prefs.get("browser.zoom.full"))
-                    [self.contentViewer.textZoom, self.contentViewer.fullZoom] =
+                    [this.contentViewer.textZoom, this.contentViewer.fullZoom] =
-                        [self.contentViewer.fullZoom, self.contentViewer.textZoom];
+                        [this.contentViewer.fullZoom, this.contentViewer.textZoom];
             });
         }
     }),

common/modules/commands.jsm

@@ -1,6 +1,6 @@
 // Copyright (c) 2006-2008 by Martin Stubenschrott <stubenschrott@vimperator.org>
 // Copyright (c) 2007-2011 by Doug Kearns <dougkearns@gmail.com>
-// Copyright (c) 2008-2012 Kris Maglione <maglione.k at Gmail>
+// Copyright (c) 2008-2013 Kris Maglione <maglione.k at Gmail>
 //
 // This work is licensed for reuse under an MIT license. Details are
 // given in the LICENSE.txt file included with this file.
@@ -583,8 +583,7 @@ var CommandHive = Class("CommandHive", Contexts.Hive, {
                 this.remove(name);
         }
 
-        let self = this;
+        let closure = () => this._map[name];
-        let closure = function () self._map[name];
 
         memoize(this._map, name, function () commands.Command(specs, description, action, extra));
         if (!extra.hidden)

common/modules/completion.jsm

@@ -135,10 +135,10 @@ var CompletionContext = Class("CompletionContext", {
              *     {@link #filters} array.
              */
             this.filterFunc = function filterFunc(items) {
-                    let self = this;
+                return this.filters
-                    return this.filters.
+                           .reduce((res, filter)
-                        reduce(function r(res, filter) res.filter(function f(item) filter.call(self, item)),
+                                        => res.filter((item) => filter.call(this, item)),
-                                items);
+                                   items);
             };
             /**
              * @property {Array} An array of predicates on which to filter the
@@ -674,7 +674,6 @@ var CompletionContext = Class("CompletionContext", {
     },
 
     getRows: function getRows(start, end, doc) {
-        let self = this;
         let items = this.items;
         let cache = this.cache.rows;
         let step = start > end ? -1 : 1;
@@ -733,12 +732,10 @@ var CompletionContext = Class("CompletionContext", {
     },
 
     split: function split(name, obj, fn) {
-        const self = this;
-
         let context = this.fork(name);
-        function alias(prop) {
+        let alias = (prop) => {
-            context.__defineGetter__(prop, function get_() self[prop]);
+            context.__defineGetter__(prop, () => this[prop]);
-            context.__defineSetter__(prop, function set_(val) self[prop] = val);
+            context.__defineSetter__(prop, (val) => this[prop] = val);
         }
         alias("_cache");
         alias("_completions");
@@ -821,7 +818,6 @@ var CompletionContext = Class("CompletionContext", {
      * context.
      */
     reset: function reset() {
-        let self = this;
         if (this.parent)
             throw Error();
 
@@ -842,7 +838,7 @@ var CompletionContext = Class("CompletionContext", {
             this.value = this._value;
             this._caret = this.value.length;
         }
-        //for (let key in (k for ([k, v] in Iterator(self.contexts)) if (v.offset > this.caret)))
+        //for (let key in (k for ([k, v] in Iterator(this.contexts)) if (v.offset > this.caret)))
         //    delete this.contexts[key];
         for each (let context in this.contexts) {
             context.hasItems = false;

common/modules/contexts.jsm

@@ -19,8 +19,6 @@ var Const = function Const(val) Class.Property({ enumerable: true, value: val })
 
 var Group = Class("Group", {
     init: function init(name, description, filter, persist) {
-        const self = this;
-
         this.name = name;
         this.description = description;
         this.filter = filter || this.constructor.defaultFilter;
@@ -171,13 +169,12 @@ var Contexts = Module("contexts", {
         Hives: Class("Hives", Class.Property, {
             init: function init(name, constructor) {
                 const { contexts } = modules;
-                const self = this;
 
                 if (this.Hive)
                     return {
                         enumerable: true,
 
-                        get: function () array(contexts.groups[self.name])
+                        get: () => array(contexts.groups[this.name])
                     };
 
                 this.Hive = constructor;

common/modules/downloads.jsm

@@ -23,21 +23,20 @@ var states = iter([v, k.slice(prefix.length).toLowerCase()]
 
 var Download = Class("Download", {
     init: function init(id, list) {
-        let self = this;
         this.download = services.downloadManager.getDownload(id);
         this.list = list;
 
         this.nodes = {
-            commandTarget: self
+            commandTarget: this
         };
         DOM.fromJSON(
             ["tr", { highlight: "Download", key: "row" },
                 ["td", { highlight: "DownloadTitle" },
                     ["span", { highlight: "Link" },
-                        ["a", { key: "launch", href: self.target.spec, path: self.targetFile.path },
+                        ["a", { key: "launch", href: this.target.spec, path: this.targetFile.path },
-                            self.displayName],
+                            this.displayName],
                         ["span", { highlight: "LinkInfo" },
-                            self.targetFile.path]]],
+                            this.targetFile.path]]],
                 ["td", { highlight: "DownloadState", key: "state" }],
                 ["td", { highlight: "DownloadButtons Buttons" },
                     ["a", { highlight: "Button", href: "javascript:0", key: "pause" }, _("download.action.Pause")],
@@ -54,19 +53,19 @@ var Download = Class("Download", {
                 ["td", { highlight: "DownloadSpeed", key: "speed" }],
                 ["td", { highlight: "DownloadTime", key: "time" }],
                 ["td", {},
-                    ["a", { highlight: "DownloadSource", key: "source", href: self.source.spec },
+                    ["a", { highlight: "DownloadSource", key: "source", href: this.source.spec },
-                        self.source.spec]]],
+                        this.source.spec]]],
             this.list.document, this.nodes);
 
-        this.nodes.launch.addEventListener("click", function (event) {
+        this.nodes.launch.addEventListener("click", (event) => {
             if (event.button == 0) {
                 event.preventDefault();
-                self.command("launch");
+                this.command("launch");
             }
         }, false);
 
-        self.updateStatus();
+        this.updateStatus();
-        return self;
+        return this;
     },
 
     get status() states[this.state],
@@ -102,7 +101,6 @@ var Download = Class("Download", {
             this.updateStatus();
         },
         launch: function launch() {
-            let self = this;
             // Behavior mimics that of the builtin Download Manager.
             function action() {
                 try {
@@ -119,13 +117,13 @@ var Download = Class("Download", {
             let file = io.File(this.targetFile);
             if (file.isExecutable() && prefs.get("browser.download.manager.alertOnEXEOpen", true))
                 this.list.modules.commandline.input(_("download.prompt.launchExecutable") + " ",
-                    function (resp) {
+                    (resp) => {
                         if (/^a(lways)$/i.test(resp)) {
                             prefs.set("browser.download.manager.alertOnEXEOpen", false);
                             resp = "yes";
                         }
                         if (/^y(es)?$/i.test(resp))
-                            action.call(self);
+                            action.call(this);
                     });
             else
                 action.call(this);

common/modules/highlight.jsm

@@ -218,11 +218,12 @@ var Highlights = Module("Highlight", {
      * @param {string} class
      */
     selector: function selector(class_)
-        let (self = this)
+        class_.replace(/(^|[>\s])([A-Z][\w-]+)\b/g,
-           class_.replace(/(^|[>\s])([A-Z][\w-]+)\b/g,
+            (m, n1, hl) => {
-            function (m, n1, hl) n1 +
+                if (this.highlight[hl] && this.highlight[hl].class != class_)
-                (self.highlight[hl] && self.highlight[hl].class != class_
+                    return n1 + this.highlight[hl].selector;
-                    ? self.highlight[hl].selector : "[dactyl|highlight~=" + hl + "]")),
+                return n1 + "[dactyl|highlight~=" + hl + "]";
+            }),
 
     groupRegexp: util.regexp(literal(/*
         ^

common/modules/javascript.jsm

@@ -765,13 +765,12 @@ var JavaScript = Module("javascript", {
             init: function init(context) {
                 init.supercall(this);
 
-                let self = this;
                 let sandbox = true || isinstance(context, ["Sandbox"]);
 
                 this.context = modules.newContext(context, !sandbox, "Dactyl REPL Context");
                 this.js = modules.JavaScript();
                 this.js.replContext = this.context;
-                this.js.newContext = function newContext() modules.newContext(self.context, !sandbox, "Dactyl REPL Temp Context");
+                this.js.newContext = () => modules.newContext(this.context, !sandbox, "Dactyl REPL Temp Context");
 
                 this.js.globals = [
                    [this.context, /*L*/"REPL Variables"],

common/modules/main.jsm

@@ -1,4 +1,4 @@
-// Copyright (c) 2009-2012 Kris Maglione <maglione.k@gmail.com>
+// Copyright (c) 2009-2013 Kris Maglione <maglione.k@gmail.com>
 //
 // This work is licensed for reuse under an MIT license. Details are
 // given in the LICENSE.txt file included with this file.
@@ -321,25 +321,24 @@ overlay.overlayWindow(Object.keys(config.overlays), function _overlay(window) ({
     },
 
     scanModules: function scanModules() {
-        let self = this;
         let { Module, modules } = this.modules;
 
-        defineModule.modules.forEach(function defModule(mod) {
+        defineModule.modules.forEach((mod) => {
             let names = Set(Object.keys(mod.INIT));
             if ("init" in mod.INIT)
                 Set.add(names, "init");
 
-            keys(names).forEach(function (name) { self.deferInit(name, mod.INIT, mod); });
+            keys(names).forEach((name) => { this.deferInit(name, mod.INIT, mod); });
         });
 
-        Module.list.forEach(function frobModule(mod) {
+        Module.list.forEach((mod) => {
             if (!mod.frobbed) {
-                modules.__defineGetter__(mod.className, function () {
+                modules.__defineGetter__(mod.className, () => {
                     delete modules[mod.className];
-                    return self.loadModule(mod.className, null, Components.stack.caller);
+                    return this.loadModule(mod.className, null, Components.stack.caller);
                 });
                 Object.keys(mod.prototype.INIT)
-                      .forEach(function (name) { self.deferInit(name, mod.prototype.INIT, mod); });
+                      .forEach((name) => { this.deferInit(name, mod.prototype.INIT, mod); });
             }
             mod.frobbed = true;
         });

common/modules/messages.jsm

@@ -147,7 +147,6 @@ var Messages = Module("messages", {
                 obj[_prop] = this.default;
                 return {
                     get: function get() {
-                        let self = this;
                         let value = this[_prop];
 
                         function getter(key, default_) function getter() messages.get([name, key].join("."), default_);

common/modules/options.jsm

@@ -1,6 +1,6 @@
 // Copyright (c) 2006-2008 by Martin Stubenschrott <stubenschrott@vimperator.org>
 // Copyright (c) 2007-2011 by Doug Kearns <dougkearns@gmail.com>
-// Copyright (c) 2008-2011 by Kris Maglione <maglione.k@gmail.com>
+// Copyright (c) 2008-2013 by Kris Maglione <maglione.k@gmail.com>
 //
 // This work is licensed for reuse under an MIT license. Details are
 // given in the LICENSE.txt file included with this file.
@@ -908,8 +908,6 @@ var Options = Module("options", {
          * @optional
          */
         add: function add(names, description, type, defaultValue, extraInfo) {
-            const self = this;
-
             if (!util.isDactyl(Components.stack.caller))
                 deprecated.warn(add, "options.add", "group.options.add");
 
@@ -927,7 +925,7 @@ var Options = Module("options", {
                 this.remove(name);
             }
 
-            let closure = function () self._optionMap[name];
+            let closure = () => this._optionMap[name];
 
             memoize(this._optionMap, name, function () Option.types[type](modules, names, description, defaultValue, extraInfo));
             for (let alias in values(names.slice(1)))

common/modules/services.jsm

@@ -1,4 +1,4 @@
-// Copyright (c) 2008-2012 Kris Maglione <maglione.k at Gmail>
+// Copyright (c) 2008-2013 Kris Maglione <maglione.k at Gmail>
 //
 // This work is licensed for reuse under an MIT license. Details are
 // given in the LICENSE.txt file included with this file.
@@ -139,7 +139,7 @@ var Services = Module("Services", {
             if (service.quiet === false)
                 throw e.stack ? e : Error(e);
 
-            if (typeof util !== "undefined")
+            if (typeof util !== "undefined" && util != null)
                 util.reportError(e);
             else
                 dump("dactyl: Service creation failed for '" + service.class + "': " + e + "\n" + (e.stack || Error(e).stack));
@@ -176,13 +176,12 @@ var Services = Module("Services", {
      *     class.
      */
     addClass: function addClass(name, class_, ifaces, init, quiet) {
-        const self = this;
         this.services[name] = { class: class_, interfaces: Array.concat(ifaces || []), method: "createInstance", init: init, quiet: quiet };
         if (init)
             memoize(this.services[name], "callable",
                     function () callable(XPCOMShim(this.interfaces)[this.init]));
 
-        this[name] = function Create() self._create(name, arguments);
+        this[name] = (function Create() this._create(name, arguments)).bind(this);
         update.apply(null, [this[name]].concat([Ci[i] for each (i in Array.concat(ifaces))]));
         return this[name];
     },

common/modules/storage.jsm

@@ -241,7 +241,6 @@ var Storage = Module("Storage", {
     },
 
     newObject: function newObject(key, constructor, params) {
-        let self = this;
         if (params == null || !isObject(params))
             throw Error("Invalid argument type");
 
@@ -261,10 +260,10 @@ var Storage = Module("Storage", {
             if (key in this && !reload)
                 throw Error("Cannot add storage key with that name.");
 
-            let load = function () self._loadData(key, params.store, params.type || myObject);
+            let load = () => this._loadData(key, params.store, params.type || myObject);
 
             this.keys[key] = new constructor(key, params.store, load, params);
-            this.keys[key].timer = new Timer(1000, 10000, function () self.save(key));
+            this.keys[key].timer = new Timer(1000, 10000, () => this.save(key));
             this.__defineGetter__(key, function () this.keys[key]);
         }
         return this.keys[key];

common/modules/styles.jsm

@@ -203,7 +203,6 @@ var Hive = Class("Hive", {
      * @param {number} index
      */
     remove: function remove(name, filter, css, index) {
-        let self = this;
         if (arguments.length == 1) {
             var matches = [name];
             name = null;
@@ -211,7 +210,7 @@ var Hive = Class("Hive", {
 
         if (filter && filter.indexOf(",") > -1)
             return filter.split(",").reduce(
-                function (n, f) n + self.removeSheet(name, f, index), 0);
+                (n, f) => n + this.removeSheet(name, f, index), 0);
 
         if (filter == undefined)
             filter = "";

common/modules/template.jsm

@@ -1,4 +1,4 @@
-// Copyright (c) 2008-2012 Kris Maglione <maglione.k at Gmail>
+// Copyright (c) 2008-2013 Kris Maglione <maglione.k at Gmail>
 //
 // This work is licensed for reuse under an MIT license. Details are
 // given in the LICENSE.txt file included with this file.
@@ -456,26 +456,24 @@ var Template = Module("Template", {
     },
 
     tabular: function tabular(headings, style, iter) {
-        let self = this;
         // TODO: This might be mind-bogglingly slow. We'll see.
         return ["table", {},
             ["tr", { highlight: "Title", align: "left" },
                 this.map(headings, function (h)
                     ["th", {}, h])],
-            this.map(iter, function (row)
+            this.map(iter, (row) =>
                 ["tr", {},
-                    self.map(Iterator(row), function ([i, d])
+                    this.map(Iterator(row), function ([i, d])
                         ["td", { style: style[i] || "" }, d])])];
     },
 
     usage: function usage(iter, format) {
-        let self = this;
 
         format = format || {};
-        let desc = format.description || function (item) self.linkifyHelp(item.description);
+        let desc = format.description || (item => this.linkifyHelp(item.description));
-        let help = format.help || function (item) item.name;
+        let help = format.help || (item => item.name);
-        function sourceLink(frame) {
+        let sourceLink = (frame) => {
-            let source = self.sourceLink(frame);
+            let source = this.sourceLink(frame);
             source[1]["dactyl:hint"] = source[2];
             return source;
         }
@@ -483,25 +481,25 @@ var Template = Module("Template", {
             format.headings ?
                 ["thead", { highlight: "UsageHead" },
                     ["tr", { highlight: "Title", align: "left" },
-                        this.map(format.headings, function (h) ["th", {}, h])]] :
+                        this.map(format.headings, (h) => ["th", {}, h])]] :
                 [],
             format.columns ?
                 ["colgroup", {},
-                    this.map(format.columns, function (c) ["col", { style: c }])] :
+                    this.map(format.columns, (c) => ["col", { style: c }])] :
                 [],
             ["tbody", { highlight: "UsageBody" },
-                this.map(iter, function (item)
+                this.map(iter, (item) =>
                     // Urgh.
                     let (name = item.name || item.names[0], frame = item.definedAt)
                         ["tr", { highlight: "UsageItem" },
                             ["td", { style: "padding-right: 2em;" },
                                 ["span", { highlight: "Usage Link" },
                                     !frame ? name :
-                                        [self.helpLink(help(item), name, "Title"),
+                                        [this.helpLink(help(item), name, "Title"),
                                          ["span", { highlight: "LinkInfo" },
                                             _("io.definedAt"), " ",
                                             sourceLink(frame)]]]],
-                            item.columns ? self.map(item.columns, function (c) ["td", {}, c]) : [],
+                            item.columns ? this.map(item.columns, (c) => ["td", {}, c]) : [],
                             ["td", {}, desc(item)]])]];
     }
 });

common/tests/functional/dactyl.jsm

@@ -40,7 +40,6 @@ function assertMessage(funcName, want, got, message) {
  * @param {MozMillController} controller The browser's MozMill controller.
  */
 function Controller(controller) {
-    var self = this;
     this.controller = controller;
 
     /**
@@ -51,13 +50,13 @@ function Controller(controller) {
 
     this.errorCount = 0;
 
-    this._countBeep = function countBeep() {
+    this._countBeep = () => {
-        self.beepCount++;
+        this.beepCount++;
     }
     this.errors = [];
-    this._countError = function countError(message, highlight) {
+    this._countError = (message, highlight) => {
         if (/\b(Error|Warning)Msg\b/.test(highlight))
-            self.errors.push(String(message));
+            this.errors.push(String(message));
     }
     this.modules.dactyl.registerObserver("beep", this._countBeep);
     this.modules.dactyl.registerObserver("echoLine", this._countError);
@@ -251,8 +250,7 @@ Controller.prototype = {
      * @param {string} message The message to display upon assertion failure. @optional
      */
     wrapAssertNoErrors: function (func, message) {
-        let self = this;
+        return () => this.assertNoErrors(func, this, arguments, message);
-        return function wrapped() self.assertNoErrors(func, this, arguments, message);
     },
 
     /**