anchor.diff:    /// overwrites the previous value.
     ///
     /// It is an error if the two [Iterable]s don't have the same length.
  +  /// Example:
  +  /// ```dart
  +  /// final keys = ['Mercury', 'Venus', 'Earth', 'Mars'];
  +  /// final values = [0.06, 0.81, 1, 0.11];
  +  /// final mapFromIterables = HashMap.fromIterables(keys, values);
  +  /// print(mapFromIterables);
  +  /// // {Earth: 1, Mercury: 0.06, Mars: 0.11, Venus: 0.81}
  +  /// ```
     factory HashMap.fromIterables(Iterable<K> keys, Iterable<V> values) {
       HashMap<K, V> map = HashMap<K, V>();
       MapBase._fillMapWithIterables(map, keys, values);
  
positive.code:   /// The keys of the key/value pairs do not need to be unique. The last
    /// occurrence of a key will simply overwrite any previous value.
    ///
    /// If no values are specified for [key] and [value] the default is the
    /// identity function.
    factory HashMap.fromIterable(Iterable iterable,
        {K Function(dynamic element)? key, V Function(dynamic element)? value}) {
      HashMap<K, V> map = HashMap<K, V>();
  
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
  