rotate method

void rotate(int steps)

In-place rotate the list steps steps to the right. If steps is negative, the list is rotated to the left.

Rotating one step to the right (steps = 1) is equivalent to list.insert(0, list.removeLast()). Rotating one step to the left (step = -1) is equivalent to list.add(list.removeAt(0)).

Implementation

void rotate(int steps) {
  final length = this.length;
  if (length > 1) {
    final count = steps % length;
    if (count != 0) {
      final other = length - count;
      if (count <= other) {
        final copy = sublist(other);
        setRange(count, length, this);
        setRange(0, copy.length, copy);
      } else {
        final copy = sublist(0, other);
        setRange(0, count, this, other);
        setRange(count, length, copy);
      }
    }
  }
}