polyfills.js

// Array Polyfills
// ---------------

(function () {

  if (!Array.prototype.indexOf) {

		// Production steps of ECMA-262, Edition 5, 15.4.4.14
		// Reference: http://es5.github.com/#x15.4.4.14

		Array.prototype.indexOf = function (searchElement /*, fromIndex */) {
			"use strict";
			if (this == null) {
				throw new TypeError();
			}
			var t = Object(this);
			var len = t.length >>> 0;
			if (len === 0) {
				return -1;
			}
			var n = 0;
			if (arguments.length > 1) {
				n = Number(arguments[1]);
				if (n != n) { // shortcut for verifying if it's NaN
					n = 0;
				} else if (n != 0 && n != Infinity && n != -Infinity) {
					n = (n > 0 || -1) * Math.floor(Math.abs(n));
				}
			}
			if (n >= len) {
				return -1;
			}
			var k = n >= 0 ? n : Math.max(len - Math.abs(n), 0);
			for (; k < len; k++) {
				if (k in t && t[k] === searchElement) {
					return k;
				}
			}
			return -1;
		};

	}

	if (!Array.prototype.lastIndexOf) {

		// Production steps of ECMA-262, Edition 5, 15.4.4.15
		// Reference: http://es5.github.com/#x15.4.4.15

		Array.prototype.lastIndexOf = function (searchElement /*, fromIndex*/) {
			"use strict";

			if (this == null)
				throw new TypeError();

			var t = Object(this);
			var len = t.length >>> 0;
			if (len === 0)
				return -1;

			var n = len;
			if (arguments.length > 1) {
				n = Number(arguments[1]);
				if (n != n)
					n = 0;
				else if (n != 0 && n != (1 / 0) && n != -(1 / 0))
					n = (n > 0 || -1) * Math.floor(Math.abs(n));
			}

			var k = n >= 0
                  ? Math.min(n, len - 1)
                  : len - Math.abs(n);

			for (; k >= 0; k--) {
				if (k in t && t[k] === searchElement)
					return k;
			}
			return -1;
		};
	}

	if (!Array.prototype.every) {

		// Production steps of ECMA-262, Edition 5, 15.4.4.16
		// Reference: http://es5.github.com/#x15.4.4.16

		Array.prototype.every = function (callbackfn /*, thisArg */) {
			"use strict";

			if (this == null)
				throw new TypeError();

			var t = Object(this);
			var len = t.length >>> 0;
			if (typeof callbackfn != "function")
				throw new TypeError();

			var thisArg = arguments[1];
			for (var i = 0; i < len; i++) {
				if (i in t && !callbackfn.call(thisArg, t[i], i, t))
					return false;
			}

			return true;
		};

	}

	if (!Array.prototype.some) {

		// Production steps of ECMA-262, Edition 5, 15.4.4.17
		// Reference: http://es5.github.com/#x15.4.4.17

		Array.prototype.some = function (callbackfn /*, thisArg */) {
			"use strict";

			if (this == null)
				throw new TypeError();

			var t = Object(this);
			var len = t.length >>> 0;
			if (typeof callbackfn != "function")
				throw new TypeError();

			var thisArg = arguments[1];
			for (var i = 0; i < len; i++) {
				if (i in t && callbackfn.call(thisArg, t[i], i, t))
					return true;
			}

			return false;
		};
	}

	if (!Array.prototype.forEach) {

		// Production steps of ECMA-262, Edition 5, 15.4.4.18
		// Reference: http://es5.github.com/#x15.4.4.18

		Array.prototype.forEach = function forEach(callbackfn, thisArg) {

			var T, k;

			if (this == null) {
				throw new TypeError("this is null or not defined");
			}

			// 1. Let O be the result of calling ToObject passing the |this| value as the argument.
			var O = Object(this);

			// 2. Let lenValue be the result of calling the Get internal method of O with the argument "length".
			// 3. Let len be ToUint32(lenValue).
			var len = O.length >>> 0; // Hack to convert O.length to a UInt32

			// 4. If IsCallable(callbackfn) is false, throw a TypeError exception.
			// See: http://es5.github.com/#x9.11
			if ({}.toString.call(callbackfn) !== "[object Function]") {
				throw new TypeError(callbackfn + " is not a function");
			}

			// 5. If thisArg was supplied, let T be thisArg; else let T be undefined.
			if (thisArg) {
				T = thisArg;
			}

			// 6. Let k be 0
			k = 0;

			// 7. Repeat, while k < len
			while (k < len) {

				var kValue;

				// a. Let Pk be ToString(k).
				//   This is implicit for LHS operands of the in operator
				// b. Let kPresent be the result of calling the HasProperty internal method of O with argument Pk.
				//   This step can be combined with c
				// c. If kPresent is true, then
				if (Object.prototype.hasOwnProperty.call(O, k)) {

					// i. Let kValue be the result of calling the Get internal method of O with argument Pk.
					kValue = O[k];

					// ii. Call the Call internal method of callback with T as the this value and
					// argument list containing kValue, k, and O.
					callbackfn.call(T, kValue, k, O);
				}
				// d. Increase k by 1.
				k++;
			}
			// 8. return undefined
		};

	}

	if (!Array.prototype.map) {

		// Production steps of ECMA-262, Edition 5, 15.4.4.19
		// Reference: http://es5.github.com/#x15.4.4.19

		Array.prototype.map = function (callbackfn, thisArg) {

			var T, A, k;

			if (this == null) {
				throw new TypeError(" this is null or not defined");
			}

			// 1. Let O be the result of calling ToObject passing the |this| value as the argument.
			var O = Object(this);

			// 2. Let lenValue be the result of calling the Get internal method of O with the argument "length".
			// 3. Let len be ToUint32(lenValue).
			var len = O.length >>> 0;

			// 4. If IsCallable(callbackfn) is false, throw a TypeError exception.
			// See: http://es5.github.com/#x9.11
			if (typeof callbackfn !== "function") {
				throw new TypeError(callbackfn + " is not a function");
			}

			// 5. If thisArg was supplied, let T be thisArg; else let T be undefined.
			if (thisArg) {
				T = thisArg;
			}

			// 6. Let A be a new array created as if by the expression new Array(len) where Array is
			// the standard built-in constructor with that name and len is the value of len.
			A = new Array(len);

			// 7. Let k be 0
			k = 0;

			// 8. Repeat, while k < len
			while (k < len) {

				var kValue, mappedValue;

				// a. Let Pk be ToString(k).
				//   This is implicit for LHS operands of the in operator
				// b. Let kPresent be the result of calling the HasProperty internal method of O with argument Pk.
				//   This step can be combined with c
				// c. If kPresent is true, then
				if (k in O) {

					// i. Let kValue be the result of calling the Get internal method of O with argument Pk.
					kValue = O[k];

					// ii. Let mappedValue be the result of calling the Call internal method of callback
					// with T as the this value and argument list containing kValue, k, and O.
					mappedValue = callbackfn.call(T, kValue, k, O);

					// iii. Call the DefineOwnProperty internal method of A with arguments
					// Pk, Property Descriptor {Value: mappedValue, : true, Enumerable: true, Configurable: true},
					// and false.

					// In browsers that support Object.defineProperty, use the following:
					// Object.defineProperty(A, Pk, { value: mappedValue, writable: true, enumerable: true, configurable: true });

					// For best browser support, use the following:
					A[k] = mappedValue;
				}
				// d. Increase k by 1.
				k++;
			}

			// 9. return A
			return A;
		};

	}

	if (!Array.prototype.filter) {

		// Production steps of ECMA-262, Edition 5, 15.4.4.20
		// Reference: http://es5.github.com/#x15.4.4.20

		Array.prototype.filter = function (callbackfn  /*, thisp */) {
			"use strict";

			if (this == null)
				throw new TypeError();

			var t = Object(this);
			var len = t.length >>> 0;
			if (typeof callbackfn != "function")
				throw new TypeError();

			var res = [];
			var thisp = arguments[1];
			for (var i = 0; i < len; i++) {
				if (i in t) {
					var val = t[i]; // in case fun mutates this
					if (callbackfn.call(thisp, val, i, t))
						res.push(val);
				}
			}

			return res;
		};

	}

	if (!Array.prototype.reduce) {

		// Production steps of ECMA-262, Edition 5, 15.4.4.21
		// Reference: http://es5.github.com/#x15.4.4.21

		Array.prototype.reduce = function (callbackfn, initialValue) {
			'use strict';

			if (null === this || 'undefined' === typeof this) {
				// At the moment all modern browsers, that support strict mode, have
				// native implementation of Array.prototype.reduce. For instance, IE8
				// does not support strict mode, so this check is actually useless.
				throw new TypeError('Array.prototype.reduce called on null or undefined');
			}

			if ('function' !== typeof callbackfn) {
				throw new TypeError(callbackfn + ' is not a function');
			}

			var index = 0, length = this.length >>> 0, value, isValueSet = false;

			if (1 < arguments.length) {
				value = initialValue;
				isValueSet = true;
			}

			for (; length > index; ++index) {
				if (!this.hasOwnProperty(index)) continue;
				if (isValueSet) {
					value = callbackfn(value, this[index], index, this);
				} else {
					value = this[index];
					isValueSet = true;
				}
			}

			if (!isValueSet) {
				throw new TypeError('Reduce of empty array with no initial value');
			}

			return value;
		};

	}

	if (!Array.prototype.reduceRight) {

		// Production steps of ECMA-262, Edition 5, 15.4.4.22
		// Reference: http://es5.github.com/#x15.4.4.22

		Array.prototype.reduceRight = function (callbackfn, initialValue) {
			'use strict';
			if (null === this || 'undefined' === typeof this) {
				// At the moment all modern browsers, that support strict mode, have
				// native implementation of Array.prototype.reduceRight. For instance,
				// IE8 does not support strict mode, so this check is actually useless.
				throw new TypeError('Array.prototype.reduceRight called on null or undefined');
			}
			if ('function' !== typeof callbackfn) {
				throw new TypeError(callbackfn + ' is not a function');
			}
			var length = this.length >>> 0, index = length - 1, value, isValueSet = false;
			if (1 < arguments.length) {
				value = initialValue;
				isValueSet = true;
			}
			for (; -1 < index; --index) {
				if (!this.hasOwnProperty(index)) continue;
				if (isValueSet) {
					value = callbackfn(value, this[index], index, this);
				} else {
					value = this[index];
					isValueSet = true;
				}
			}
			if (!isValueSet) {
				throw new TypeError('Reduce of empty array with no initial value');
			}
			return value;
		};

	}

})();

// String Polyfills
// ----------------

(function () {

	if (!String.prototype.trim) {

		String.prototype.trim = function () {
			return this.replace(/^\s+|\s+$/g, '');
		};

	}

	if (!String.format) {

		String.format = function () {

			var
				formatString = arguments[0],
				args = [],
				result = '',
				regex = /{(\d+)}$/g;

			if (arguments[1] instanceof Array) {
				args = arguments[1];
			} else {
				for (var i = 1; i < arguments.length; i++) {
					args.push(arguments[i]);
				}
			}

			for (var i = 0; i < formatString.length; i++) {
				result += formatString[i];

				if (result.match(regex)) {
					result = result.replace(regex, function (match, number) {
						var index = parseInt(number, 10);
						var arg = args[index];

						if (typeof arg === 'undefined') {
							throw new Error('The index of a format item is less than zero, or greater than or equal to the number of arguments in the arguments list.');
						}

						return arg;
					});
				}
			}

			return result;

		};
	}

})();

// Window Polyfills
// ----------------

(function () {

	// Credit to Erik Möller
	// URL: http://my.opera.com/emoller/blog/2011/12/20/requestanimationframe-for-smart-er-animating

	var
        lastTime = 0,
        vendors = ['ms', 'moz', 'webkit', 'o'];

	for (var x = 0; x < vendors.length && !window.requestAnimationFrame; ++x) {
		window.requestAnimationFrame = window[vendors[x] + 'RequestAnimationFrame'];
		window.cancelAnimationFrame = window[vendors[x] + 'CancelAnimationFrame'] || window[vendors[x] + 'CancelRequestAnimationFrame'];
	}

	if (!window.requestAnimationFrame) {

		window.requestAnimationFrame = function (callback, element) {
			var currTime = new Date().getTime();
			var timeToCall = Math.max(0, 16 - (currTime - lastTime));
			var id = window.setTimeout(function () { callback(currTime + timeToCall); }, timeToCall);
			lastTime = currTime + timeToCall;
			return id;
		};

	}

	if (!window.cancelAnimationFrame) {

		window.cancelAnimationFrame = function (id) {
			clearTimeout(id);
		};

	}

}());