description

# HashMap<K, V>.fromIterable constructor

HashMap<K, V>.fromIterable(

1. Iterable iterable, {
2. K key(
   1. dynamic element
   )?,
3. V value(
   1. dynamic element
   )?,

})

Creates a HashMap where the keys and values are computed from the `iterable`.

For each element of the `iterable` this constructor computes a key/value pair, by applying `key` and `value` respectively.

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. Example:

    final numbers = [11, 12, 13, 14];
    final mapFromIterable = HashMap<int, int>.fromIterable(numbers,
        key: (i) => i, value: (i) => i * i);
    print(mapFromIterable); // {11: 121, 12: 144, 13: 169, 14: 196}

## Implementation

    factory HashMap.fromIterable(
      Iterable iterable, {
      K Function(dynamic element)? key,
      V Function(dynamic element)? value,
    }) {
      HashMap<K, V> map = HashMap<K, V>();
      MapBase._fillMapWithMappedIterable(map, iterable, key, value);
      return map;
    }