length property

@override int length

The number of elements in this.

Counting all elements may involve iterating through all elements and can therefore be slow. Some iterables have a more efficient way to find the number of elements. These must override the default implementation of length.

Implementation

@override
int get length {
  final len = (_last - first).abs() ~/ step.abs();
  final len2 = len - (first + len * step == _last ? 1 : 0);
  return len2 > 0 ? len2 : 0;
}