FrankerFaceZ/src/shims.js

Array.prototype.equals = function (array) {
	// if the other array is a falsy value, return
	if (!array)
		return false;

	// compare lengths - can save a lot of time 
	if (this.length != array.length)
		return false;

	for (var i = 0, l=this.length; i < l; i++) {
		// Check if we have nested arrays
		if (this[i] instanceof Array && array[i] instanceof Array) {
			// recurse into the nested arrays
			if (!this[i].equals(array[i]))
				return false;
		}
		else if (this[i] != array[i]) { 
			// Warning - two different object instances will never be equal: {x:20} != {x:20}
			return false;
		}
	}
	return true;
}