Very fast left pad, anything (JavaScript)

leftPad.js

leftPad = function leftPad(value, size, pad) { // very very fast
	if (value.length < size) {
		size -= value.length;
		var res = '';
		for(;;) {
	        if (size & 1) res += pad;
	        size >>= 1;
	        if (size) pad += pad;
	        else break;
	    }
		return res + value;
	}
	return value;
}