We study Javascript by going through the bones of Backbone.js

(function(root, factory) { //      if (typeof define === 'function' && define.amd) { //  ,     define  amd, define(['underscore', 'jquery', 'exports'], function(_, $, exports) { //      //   -        root.Backbone = factory(root, exports, _, $); }); //   Node,  jQuery   } else if (typeof exports !== 'undefined') { var _ = require('underscore'); factory(root, exports, _); //    } else { root.Backbone = factory(root, {}, root._, (root.jQuery || root.Zepto || root.ender || root.$)); } }(this, function(root, Backbone, _, $) { })); 

 function(root, Backbone, _, $) { //  ,       Backbone var previousBackbone = root.Backbone; //          var array = []; var push = array.push; var slice = array.slice; var splice = array.splice; //  Backbone.VERSION = '1.1.2'; //       Backbone.$ = $; //  , ,     Backbone.noConflict = function() { root.Backbone = previousBackbone; return this; }; //     Backbone.emulateHTTP = false; Backbone.emulateJSON = false; //  ,       //   ,   ,    - var Events = Backbone.Events = { //  ,  ,    obj.trigger(' '); on: function(name/* */, callback/**/, context/* ,   this  */) { }, // ,    once: function(name, callback, context) { }, //    off: function(name, callback, context) { }, //    trigger: function(name) { }, //   -     stopListening: function(obj, name, callback) {}; //    ,  -  this     var listenMethods = {listenTo: 'on', listenToOnce: 'once'}; //     ,     Events.bind = Events.on; Events.unbind = Events.off; //  Backbone     _.extend(Backbone, Events); //  . //       - var Model = Backbone.Model = function(attributes, options) {}; //   ,    _.extend(Model.prototype, Events/*      */, {/*  */}); //   //     ,    var Collection = Backbone.Collection = function(models, options) { }; // ,   ,   _.extend(Collection.prototype, Events, {}); //   //  -   ,            jQuery var View = Backbone.View = function(options) {}; //  _.extend(View.prototype, Events, {}); //   /    // -   jQuery.ajax Backbone.sync = function(method, model, options) {}; //         //      ,      //     history var Router = Backbone.Router = function(options) {}; _.extend(Router.prototype, Events, {}); //     ,   //    var History = Backbone.History = function() {}; _.extend(History.prototype, Events, {}); // C  Backbone.history = new History; //    return Backbone; } 

 var extend = function(protoProps/*   */, staticProps/*   */) { var parent = this; //  ,    var child; //  ,   if (protoProps && _.has(protoProps, 'constructor')) { //       child = protoProps.constructor; //       } else { //        child = function(){ return parent.apply(this, arguments); }; //  this    child } //    child ,      _.extend(child, parent, staticProps); //  ,      //  : child.staticProp(); //  child  ,   var Surrogate = function(){ this.constructor = child; }; //    Surrogate.prototype = parent.prototype; //     parent child.prototype = new Surrogate; //     parent //     ,  : var x = new child; x.protoProp(); if (protoProps) _.extend(child.prototype, protoProps); // ,   , ,       child.__super__ = parent.prototype; return child; }; //           Model.extend = Collection.extend = Router.extend = View.extend = History.extend = extend; 

  //           var events = this._events[name] || (this._events[name] = []); //   this -  Events //    ,      _.extend(Model.prototype, Events); //  ,          (function(root, factory) {}(this, function(root, Backbone, _, $) {})) //    // ,  once: function(name, callback, context) { var self = this; //  ,    var once = _.once(function() { self.off(name, once); //  ,          callback.apply(this, arguments); }); once._callback = callback; //         ,          return this.on(name, once, context); // -     }, trigger: function(name) { var args = slice.call(arguments, 1); //     if (events) triggerEvents(events, args); // ,     ,    if (allEvents) triggerEvents(allEvents, arguments); // ,     ,       return this; } //          var triggerEvents = function(events, args) { var ev, i = -1, l = events.length, a1 = args[0], a2 = args[1], a3 = args[2]; switch (args.length) { case 0: while (++i < l) (ev = events[i]).callback.call(ev.ctx); return; //   this  ev.ctx case 1: while (++i < l) (ev = events[i]).callback.call(ev.ctx, a1); return; case 2: while (++i < l) (ev = events[i]).callback.call(ev.ctx, a1, a2); return; case 3: while (++i < l) (ev = events[i]).callback.call(ev.ctx, a1, a2, a3); return; //   ,     : ev.ctx.callback(args[0], args[1], args[2]  ..) default: while (++i < l) (ev = events[i]).callback.apply(ev.ctx, args); return; } }; // ,      ,   ,     this.initialize.apply(this, arguments); has: function(attr) { //    return this.get(attr) != null; //       } // ,    ,     if (!diff) return this.hasChanged() ? _.clone(this.changed) : false; fetch: function(options) { options = options ? _.clone(options) : {}; //         if (options.parse === void 0) options.parse = true; //    -    var model = this; //    ,     var success = options.success; //    options.success = function(resp) { //  ,        ,    ,   if (!model.set(model.parse(resp, options), options)) return false; if (success) success(model, resp, options); //  ,    model.trigger('sync', model, resp, options); }; wrapError(this, options); // error    ,     return this.sync('read', this, options); //           }, //   return new this.constructor(this.attributes); //    var modelMethods = ['keys', 'values', 'pairs', 'invert', 'pick', 'omit']; _.each(modelMethods, function(method) { Model.prototype[method] = function() { //     var args = slice.call(arguments); //     args.unshift(this.attributes); // c     return _[method].apply(_, args); //     Underscore }; }); attrs instanceof Model //      //       this[first ? 'find' : 'filter'](function(model) { for (var key in attrs) { if (attrs[key] !== model.get(key)) return false; } return true; }); this.models.sort(_.bind(this.comparator, this)/*  ,        comparator.call(this)*/); 

  //     () var eventSplitter = /\s+/; //     //         var names = name.split(eventSplitter) //      ,      //    ,      id c    base.replace(/([^\/])$/, '$1/') + encodeURIComponent(this.id) //       _routeToRegExp: function(route) { route = route.replace(escapeRegExp, '\\$&') .replace(optionalParam, '(?:$1)?') .replace(namedParam, function(match, optional) { return optional ? match : '([^/?]+)'; }) .replace(splatParam, '([^?]*?)'); return new RegExp('^' + route + '(?:\\?([\\s\\S]*))?$'); } //      var params = route.exec(fragment).slice(1); //       var match = (window || this).location.href.match(/#(.*)$/); 

  //     $: function(selector) { return this.$el.find(selector); }, this.el = this.$el[0]; //     method = _.bind(method, this); //  , ,        eventName += '.delegateEvents' + this.cid; //      if (selector === '') { this.$el.on(eventName, method); //   } else { // .. jQuery  , ,   -     this.$el.on(eventName, selector, method); } this.$el.off('.delegateEvents' + this.cid); //   - //       var $el = Backbone.$('<' + _.result(this, 'tagName') + '>').attr(attrs); //    var xhr = options.xhr = Backbone.ajax(_.extend(params, options)); Backbone.ajax = function() { return Backbone.$.ajax.apply(Backbone.$, arguments); }; 

  //        if (typeof window !== 'undefined') { this.location = window.location; this.history = window.history; } //   fragment = decodeURI(this.location.pathname + this.location.search) Backbone.$(window).on('popstate', this.checkUrl); //     Backbone.$(window).on('hashchange', this.checkUrl); this.location.replace(this.root + '#' + this.fragment); //   //      Backbone.$(window).off('popstate', this.checkUrl).off('hashchange', this.checkUrl); 

  //       Backbone       root.Backbone = factory(root, {}/*  */, root._, (root.jQuery || root.Zepto || root.ender || root.$)) // ,   ,  on: function(name, callback, context) { //          if (!eventsApi(this, 'on', name, [callback, context]) || !callback) return this; //      } off: function(name, callback, context) { var retain, ev, events, names, i, l, j, k; //     ,   -      return this; }, //         if (obj) (listeningTo = {})[obj._listenId] = obj; //     delete this._listeningTo[id] //       var remove = !name && !callback; //      //   eventsApi, ,   x.on({     }) for (var key in name) { obj[action].apply(obj, [key, name[key]].concat(rest)); //       x.on(''); } //    ( ) var listenMethods = {listenTo: 'on', listenToOnce: 'once'}; _.each(listenMethods, function(implementation, method) { Events[method] = function(obj, name, callback) { //      obj[implementation](name, callback, this); return this; }; }); //   ,    var attrs = attributes || {}; options || (options = {}); unset: function(attr, options) { return this.set(attr, void 0/* undefined*/, _.extend({}, options, {unset: true})/*     */); } //         if (key == null || typeof key === 'object') { attrs = key; options = val; } else { (attrs = {})[key] = val; } //       . method = this.isNew() ? 'create' : (options.patch ? 'patch' : 'update'); //   ,   ,     , ,  var iterator = _.isFunction(value) ? value : function(model) { return model.get(value); }; //        var methodMap = { 'create': 'POST', 'update': 'PUT', 'patch': 'PATCH', 'delete': 'DELETE', 'read': 'GET' }; //    throw new Error('A "url" property or function must be specified'); //    ,     var wrapError = function(model, options) { var error = options.error; options.error = function(resp) { if (error) error(model, resp, options); model.trigger('error', model, resp, options); }; };