anchor.diff:    ///
     /// If multiple [entries] have the same key,
     /// later occurrences overwrite the earlier ones.
  +  ///
  +  /// Example:
  +  /// ```dart
  +  /// final numbers = [11, 12, 13, 14];
  +  /// final map = HashMap.fromEntries(numbers.map((i) => MapEntry(i, i * i)));
  +  /// print(map); // {11: 121, 12: 144, 13: 169, 14: 196}
  +  /// ```
     @Since("2.1")
     factory HashMap.fromEntries(Iterable<MapEntry<K, V>> entries) =>
         HashMap<K, V>()..addEntries(entries);
  
positive.code:   /// new keys. If [equals] is omitted, the key's own [Object.==] is used
    /// instead.
    ///
    /// Similar, if [hashCode] is provided, it is used to produce a hash value
    /// for keys in order to place them in the map. If [hashCode] is omitted,
    /// the key's own [Object.hashCode] is used.
    ///
    /// The used `equals` and `hashCode` method should always be consistent,
    /// so that if `equals(a, b)` then `hashCode(a) == hashCode(b)`. The hash
    /// of an object, or what it compares equal to, should not change while the
    /// object is a key in the map. If it does change, the result is
    /// unpredictable.
  
negative.code: typedef _Hasher<K> = int Function(K object);
  
  /// A hash-table based implementation of [Map].
  ///
  /// The [HashMap] is unordered (the order of iteration is not guaranteed).
  ///
  /// The keys of a `HashMap` must have consistent [Object.==]
  /// and [Object.hashCode] implementations. This means that the `==` operator
  