/* extensions */
Array.prototype.indexOf = function (v) {
	for (var i = 0; i < this.length; i++) {
		if (this[i] == v) return i;
	}
	return -1;
};

Array.prototype.without = function (v) {
	try {
		return jQuery.grep(this, function(value) { return value != v; });
	} catch (e) {
		return this;
	}
};