code: function range(start, stop) {
    if (arguments.length <= 1) {
      stop = start || 0;
      start = 0;
    }
  
    var length = Math.max(stop - start, 0);
    var idx = 0;
    var arr = new Array(length);
  
    while(idx < length) {
      arr[idx++] = start;
      start += 1;
    }
  
    return arr;
  }
docs: Slighlty modified from underscore source