Knockout: Code style

architecture-examples/knockoutjs/js/app.js

+/*global ko, crossroads */
 (function() {
 	'use strict';
-	var ENTER_KEY = 13;
 
-	// trim polyfill
-	if(!String.prototype.trim) {
-		String.prototype.trim = function() {
-			return this.replace(/^\s+|\s+$/g, '');
-		};
-	}
+	var ENTER_KEY = 13;
 
 	// a custom binding to handle the enter key (could go in a separate library)
 	ko.bindingHandlers.enterKey = {
-		init: function(element, valueAccessor, allBindingsAccessor, data) {
+		init: function( element, valueAccessor, allBindingsAccessor, data ) {
 			var wrappedHandler, newValueAccessor;
 
 			// wrap the handler with a check for the enter key
-			wrappedHandler = function(data, event) {
-				if(event.keyCode === ENTER_KEY) {
-					valueAccessor().call(this, data, event);
+			wrappedHandler = function( data, event ) {
+				if ( event.keyCode === ENTER_KEY ) {
+					valueAccessor().call( this, data, event );
 				}
 			};
 
@@ -29,40 +24,41 @@
 			};
 
 			// call the real event binding's init function
-			ko.bindingHandlers.event.init(element, newValueAccessor, allBindingsAccessor, data);
+			ko.bindingHandlers.event.init( element, newValueAccessor, allBindingsAccessor, data );
 		}
 	};
 
 	// wrapper to hasfocus that also selects text and applies focus async
 	ko.bindingHandlers.selectAndFocus = {
-		init: function(element, valueAccessor, allBindingsAccessor) {
-			ko.bindingHandlers.hasfocus.init(element, valueAccessor, allBindingsAccessor);
-			ko.utils.registerEventHandler(element, 'focus', function() {
+		init: function( element, valueAccessor, allBindingsAccessor ) {
+			ko.bindingHandlers.hasfocus.init( element, valueAccessor, allBindingsAccessor );
+			ko.utils.registerEventHandler( element, 'focus', function() {
 				element.select();
 			});
 		},
-		update: function(element, valueAccessor) {
-			ko.utils.unwrapObservable(valueAccessor()); // for dependency
+		update: function( element, valueAccessor ) {
+			ko.utils.unwrapObservable( valueAccessor() ); // for dependency
 			// ensure that element is visible before trying to focus
 			setTimeout(function() {
-				ko.bindingHandlers.hasfocus.update(element, valueAccessor);
+				ko.bindingHandlers.hasfocus.update( element, valueAccessor );
 			}, 0);
 		}
 	};
 
 	// represent a single todo item
-	var Todo = function(title, completed) {
-		this.title = ko.observable(title);
-		this.completed = ko.observable(completed);
-		this.editing = ko.observable(false);
+	var Todo = function( title, completed ) {
+		this.title = ko.observable( title );
+		this.completed = ko.observable( completed );
+		this.editing = ko.observable( false );
 	};
 
 	// our main view model
-	var ViewModel = function(todos) {
+	var ViewModel = function( todos ) {
 		var self = this;
+
 		// map array of passed in todos to an observableArray of Todo objects
-		self.todos = ko.observableArray(ko.utils.arrayMap(todos, function(todo) {
-			return new Todo(todo.title, todo.completed);
+		self.todos = ko.observableArray(ko.utils.arrayMap( todos, function( todo ) {
+			return new Todo( todo.title, todo.completed );
 		}));
 
 		// store the new todo value being entered
@@ -71,11 +67,15 @@
 		self.showMode = ko.observable('all');
 
 		self.filteredTodos = ko.computed(function() {
-			switch(self.showMode()) {
+			switch( self.showMode() ) {
 				case 'active':
-					return self.todos().filter(function(todo) { return !todo.completed(); });
+					return self.todos().filter(function( todo ) {
+						return !todo.completed();
+					});
 				case 'completed':
-					return self.todos().filter(function(todo) { return todo.completed(); });
+					return self.todos().filter(function( todo ) {
+						return todo.completed();
+					});
 				default:
 					return self.todos();
 			}
@@ -84,40 +84,41 @@
 		// add a new todo, when enter key is pressed
 		self.add = function() {
 			var current = self.current().trim();
-			if(current) {
-				self.todos.push(new Todo(current));
+			if ( current ) {
+				self.todos.push( new Todo( current ) );
 				self.current('');
 			}
 		};
 
 		// remove a single todo
-		self.remove = function(todo) {
-			self.todos.remove(todo);
+		self.remove = function( todo ) {
+			self.todos.remove( todo );
 		};
 
 		// remove all completed todos
 		self.removeCompleted = function() {
-			self.todos.remove(function(todo) {
+			self.todos.remove(function( todo ) {
 				return todo.completed();
 			});
 		};
 
 		// edit an item
-		self.editItem = function(item) {
-			item.editing(true);
+		self.editItem = function( item ) {
+			item.editing( true );
 		};
 
 		// stop editing an item.  Remove the item, if it is now empty
-		self.stopEditing = function(item) {
-			item.editing(false);
-			if(!item.title().trim()) {
-				self.remove(item);
+		self.stopEditing = function( item ) {
+			item.editing( false );
+
+			if ( !item.title().trim() ) {
+				self.remove( item );
 			}
 		};
 
 		// count of all completed todos
 		self.completedCount = ko.computed(function() {
-			return ko.utils.arrayFilter(self.todos(), function(todo) {
+			return ko.utils.arrayFilter( self.todos(), function( todo ) {
 				return todo.completed();
 			}).length;
 		});
@@ -135,42 +136,50 @@
 			},
 			// set all todos to the written value (true/false)
 			write: function(newValue) {
-				ko.utils.arrayForEach(self.todos(), function(todo) {
+				ko.utils.arrayForEach( self.todos(), function( todo ) {
 					// set even if value is the same, as subscribers are not notified in that case
-					todo.completed(newValue);
+					todo.completed( newValue );
 				});
 			}
 		});
 
 		// helper function to keep expressions out of markup
-		self.getLabel = function(count) {
-			return ko.utils.unwrapObservable(count) === 1 ? 'item' : 'items';
+		self.getLabel = function( count ) {
+			return ko.utils.unwrapObservable( count ) === 1 ? 'item' : 'items';
 		};
 
 		// internal computed observable that fires whenever anything changes in our todos
 		ko.computed(function() {
 			// store a clean copy to local storage, which also creates a dependency on the observableArray and all observables in each item
-			localStorage.setItem('todos-knockout', ko.toJSON(self.todos));
-
+			localStorage.setItem('todos-knockout', ko.toJSON( self.todos ) );
 		}).extend({
 			throttle: 500
 		}); // save at most twice per second
 	};
 
 	// check local storage for todos
-	var todos = ko.utils.parseJson(localStorage.getItem('todos-knockout'));
+	var todos = ko.utils.parseJson( localStorage.getItem('todos-knockout') );
 
 	// bind a new instance of our view model to the page
-	var viewModel = new ViewModel(todos || [])
-	ko.applyBindings(viewModel);
+	var viewModel = new ViewModel( todos || [] );
+	ko.applyBindings( viewModel );
 
 	//setup crossroads
-	crossroads.addRoute('all', function() { viewModel.showMode('all'); });
-	crossroads.addRoute('active', function() { viewModel.showMode('active'); });
-	crossroads.addRoute('completed', function() { viewModel.showMode('completed'); });
+	crossroads.addRoute('all', function() {
+		viewModel.showMode('all');
+	});
+
+	crossroads.addRoute('active', function() {
+		viewModel.showMode('active');
+	});
+
+	crossroads.addRoute('completed', function() {
+		viewModel.showMode('completed');
+	});
 
 	window.onhashchange = function() {
-		crossroads.parse(location.hash.replace("#", ""));
+		crossroads.parse( location.hash.replace('#', '') );
 	};
-	crossroads.parse(location.hash.replace("#", ""));
-})();
\ No newline at end of file
+
+	crossroads.parse( location.hash.replace('#', '') );
+}());
\ No newline at end of file