code-reuse-patterns/borrowing-methods.html

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		<title>JavaScript Patterns</title>
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		<script>
			/* Title: Borrowing Methods
			 Description: reuse one or two methods of an existing object without forming a parent-child relationship with that object
			 */

			function f() {
				var args = [].slice.call(arguments, 1, 3);
				return args;
			}

			var one = {
				name:'object',
				say:function (greet) {
					return greet + ', ' + this.name;
				}
			};

			// test
			console.log(one.say('hi')); // "hi, object"

			var two = {
				name:'another object'
			};
			
			// apply two to original object one.
			console.log(one.say.apply(two, ['hello'])); // "hello, another object"

			// assigning to a variable
			// `this` will point to the global object
			var say = one.say;
			console.log(say('hoho')); // "hoho, undefined"

			// passing as a callback
			var yetanother = {
				name:'Yet another object',
				method:function (callback) {
					return callback('Hola');
				}
			};
			console.log(yetanother.method(one.say)); // "Hola, undefined"

			function bind(o, m) {
				return function () {
					return m.apply(o, [].slice.call(arguments));
				};
			}

			var twosay = bind(two, one.say);
			console.log(twosay('yo')); // "yo, another object"


			// ECMAScript 5 adds a method bind() to Function.prototype, making it just as easy to use as apply() and call().

			if (typeof Function.prototype.bind === 'undefined') {
				Function.prototype.bind = function (thisArg) {
					var fn = this,
							slice = Array.prototype.slice,
							args = slice.call(arguments, 1);
					return function () {
						return fn.apply(thisArg, args.concat(slice.call(arguments)));
					};
				};
			}

			var twosay2 = one.say.bind(two);
			console.log(twosay2('Bonjour')); // "Bonjour, another object"

			var twosay3 = one.say.bind(two, 'Enchanté');
			console.log(twosay3()); // "Enchanté, another object"


			// reference
			// http://shop.oreilly.com/product/9780596806767.do
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