arange function
Implementation
Array arange({double start = 0, required double end, double step = 1}) {
  assert(step != 0);
  var _range = range(start: 0, end: ((end - start) / step).ceil(), step: 1);
  var result = [
    for (var x in _range) [x * step + start]
  ];
  return Array(values: result);
}