Add Grant class files extend and promote to createjs/utils

Author: OJay Robinson

src/createjs/utils/extend.js

@@ -0,0 +1,63 @@
+/*
+* core
+* Visit http://createjs.com/ for documentation, updates and examples.
+*
+* Copyright (c) 2010 gskinner.com, inc.
+* 
+* Permission is hereby granted, free of charge, to any person
+* obtaining a copy of this software and associated documentation
+* files (the "Software"), to deal in the Software without
+* restriction, including without limitation the rights to use,
+* copy, modify, merge, publish, distribute, sublicense, and/or sell
+* copies of the Software, and to permit persons to whom the
+* Software is furnished to do so, subject to the following
+* conditions:
+* 
+* The above copyright notice and this permission notice shall be
+* included in all copies or substantial portions of the Software.
+* 
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+* OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+/**
+ * @module CreateJS
+ */
+"use strict";
+
+// namespace:
+this.createjs = this.createjs||{};
+
+/**
+ * @class Utility Methods
+ */
+
+/**
+ * Sets up the prototype chain and constructor property for a new class.
+ * 
+ * This should be called right after creating the class constructor.
+ * 
+ * 	function MySubClass() {}
+ * 	createjs.extend(MySubClass, MySuperClass); // returns the prototype
+ * 	ClassB.prototype.doSomething = function() { }
+ * 	
+ * 	var foo = new MySubClass();
+ * 	console.log(foo instanceof MySuperClass); // true
+ * 	console.log(foo.prototype.constructor === MySubClass); // true
+ * 
+ * @method extends
+ * @param {Function} subclass The subclass.
+ * @param {Function} superclass The superclass to extend.
+ * @return {Function} Returns the subclass's new prototype.
+ */
+createjs.extend = function(subclass, superclass) {
+	function o() { this.constructor = subclass; }
+	o.prototype = superclass.prototype;
+	return (subclass.prototype = new o());
+};

src/createjs/utils/promote.js

@@ -0,0 +1,88 @@
+/*
+* core
+* Visit http://createjs.com/ for documentation, updates and examples.
+*
+* Copyright (c) 2010 gskinner.com, inc.
+* 
+* Permission is hereby granted, free of charge, to any person
+* obtaining a copy of this software and associated documentation
+* files (the "Software"), to deal in the Software without
+* restriction, including without limitation the rights to use,
+* copy, modify, merge, publish, distribute, sublicense, and/or sell
+* copies of the Software, and to permit persons to whom the
+* Software is furnished to do so, subject to the following
+* conditions:
+* 
+* The above copyright notice and this permission notice shall be
+* included in all copies or substantial portions of the Software.
+* 
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+* OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+/**
+ * @module CreateJS
+ */
+"use strict";
+
+// namespace:
+this.createjs = this.createjs||{};
+
+/**
+ * @class Utility Methods
+ */
+
+/**
+ * Promotes any methods on the super class that were overridden, by creating an alias in the format `SuperClassName_methodName`.
+ * An alias to the super class's constructor is always added in the format `SuperClassName_constructor`.
+ * This allows the subclass to call super class methods without using `function.call`, providing better performance.
+ * 
+ * For example, if `MySubClass` extends `MySuperClass`, and both define a `draw` method, then calling `promote(MySubClass)`
+ * would: add a `MySuperClass_constructor` method to MySubClass and promote the `draw` method on MySuperClass to the
+ * prototype of MySubClass as `MySuperClass_draw`.
+ * 
+ * This should be called after the class's prototype is fully defined.
+ * 
+ * 	function ClassA(name) {
+ * 		this.name = name;
+ * 	}
+ * 	ClassA.prototype.greet = function() {
+ * 		return "Hello "+this.name;
+ * 	}
+ * 	
+ * 	function ClassB(name, punctuation) {
+ * 		this.ClassA_constructor(name);
+ * 		this.punctuation = punctuation;	
+ * 	}
+ * 	createjs.extend(ClassB, ClassA);
+ * 	ClassB.prototype.greet = function() {
+ * 		return this.ClassA_greet()+this.punctuation;
+ * 	}
+ * 	createjs.promote(ClassB);
+ * 	
+ * 	var foo = new ClassB("World", "!?!");
+ * 	console.log(foo.greet()); // Hello World!?!
+ * 
+ * @method extends
+ * @param {Function} subclass The subclass to promote super class methods on.
+ * @param {String} [superclassName] The name of the superclass. This is only necessary if the constructor is an anonymous function (`MyClass = function()` instead of `function MyClass()`).
+ * @return {Function} Returns the subclass.
+ */
+createjs.promote = function(subclass, superclassName) {
+	var subP = subclass.prototype, supP = (Object.getPrototypeOf&&Object.getPrototypeOf(subP))||subP.__proto__;
+	if (supP) {
+		superclassName = superclassName || supP.constructor.name || /^function\s+([^\s\(]+)\s*\(/.exec(String(supP.constructor))[1];
+
+		subP[superclassName + "_constructor"] = supP.constructor; // constructor is not always innumerable
+		for (var n in supP) {
+			if (subP[n] && (typeof supP[n] == "function")) { subP[superclassName + "_" + n] = supP[n]; }
+		}
+	}
+	return subclass;
+};