hash method

*<Null safety>*

• @override

int hash (Map<K, V>? map) override

Implementation

@override
int hash(Map<K, V>? map) {
  if (map == null) return null.hashCode;
  var hash = 0;
  for (var key in map.keys) {
    var keyHash = _keyEquality.hash(key);
    var valueHash = _valueEquality.hash(map[key] as V);
    hash = (hash + 3 * keyHash + 7 * valueHash) & _HASH_MASK;
  }
  hash = (hash + (hash << 3)) & _HASH_MASK;
  hash ^= (hash >> 11);
  hash = (hash + (hash << 15)) & _HASH_MASK;
  return hash;
}