operator [] method

V? operator [](
  1. Object? key

The value for the given key, or null if key is not in the map.

Some maps allow null as a value. For those maps, a lookup using this operator cannot distinguish between a key not being in the map, and the key being there with a null value. Methods like containsKey or putIfAbsent can be used if the distinction is important.


V? operator [](Object? key) {
  if (!_validKey(key)) return null;
  if (_root != null) {
    int comp = _splay(key as dynamic);
    if (comp == 0) {
      return _root!.value;
  return null;