Javascript String padL(width, pad)

String.prototype.padL = function(width, pad) {
 if (!width || width < 1)
  return this;//  w  ww .  j  av  a 2  s. co  m

 if (!pad)
  pad = " ";
 var length = width - this.length;
 if (length < 1)
  return this.substr(0, width);

 return (String.repeat(pad, length) + this).substr(0, width);
};