itsa-jsext/lib/function.js

Extensions to native javascript-objects, all within the itsa_ namespace

/**
 *
 * Pollyfils for often used functionality for Functions
 *
 * <i>Copyright (c) 2014 ITSA - https://github.com/itsa</i>
 * New BSD License - http://choosealicense.com/licenses/bsd-3-clause/
 *
 * @module js-ext
 * @submodule lib/function.js
 * @class Function
 *
*/

"use strict";

(function(FunctionPrototype) {
	/**
	 * Sets the context of which the function will be execute. in the
	 * supplied object's context, optionally adding any additional
	 * supplied parameters to the end of the arguments the function
	 * is executed with.
	 *
	 * @method itsa_rbind
	 * @param [context] {Object} the execution context.
	 *        The value is ignored if the bound function is constructed using the new operator.
	 * @param [args*] {any} args* 0..n arguments to append to the end of
	 *        arguments collection supplied to the function.
	 * @return {function} the wrapped function.
	 */
	FunctionPrototype.itsa_rbind = function (context /*, args* */ ) {
		var thisFunction = this,
			arrayArgs,
			slice = Array.prototype.slice;
		context || (context = this);
		if (arguments.length > 1) {
			// removing `context` (first item) by slicing it out:
			arrayArgs = slice.call(arguments, 1);
		}

		return (arrayArgs ?
			function () {
				// over here, `arguments` will be the "new" arguments when the final function is called!
				return thisFunction.apply(context, slice.call(arguments, 0).concat(arrayArgs));
			} :
			function () {
				// over here, `arguments` will be the "new" arguments when the final function is called!
				return thisFunction.apply(context, arguments);
			}
		);
	};

}(Function.prototype));