offset method

Tree offset(
  1. int start, [
  2. int end = 0
])

Implementation

Tree offset(int start, [int end = 0]) {
  var s = start;
  var e = end;
  if (s > e) {
    final tmp = s;
    s = e;
    e = tmp;
  }
  if (s < 0) s = 0;
  if (e < 0 || e > _children.length) e = _children.length;
  _offsetStart = s;
  _offsetEnd = e;
  return this;
}