permutate

permutate.js

function permutate(fn) {
	var result = [];
	var queue = [Array.slice(arguments, 1)];

	while (queue.length) {
		var args = queue.shift();
		for (var i = 0, len = args.length; i < len; i++) {
			var arg = args[i];
			if (arg instanceof Array) break;
		}
		if (i === len) {
			result.push(fn.apply(this, args));
		} else {
			for (var j = 0, len = arg.length; j < len; j++) {
				args[i] = arg[j];
				queue.push(args.concat());
			}
		}
	}

	return result;
}
permutate(function(a, b, c) a + b + c, [100, 200], [10, 20], [1, 2]).toSource();
// [111, 112, 121, 122, 211, 212, 221, 222]