text: 
  app.range = function (start, end, step, offset) { return Array.apply(null, Array((Math.abs(end - start) + ((offset||0)*2))/(step||1)+1)) .map(function(_, i) { return start < end ? i*(step||1) + start - (offset||0) :  (start - (i*(step||1))) + (offset||0) }) }