Javascript Object noCalvesYet()

Object.prototype.noCalvesYet = function() {
  return this.type == "cow" && this.hadCalf == null;
};

Object.prototype.noCalvesYet = function(){
  if (this.type == "cow" && this.hadCalf == null) {
    return true;//from   ww w .  j  a  v a  2 s  .  c  om
  } else {
    return false;
  }
};