HashMap<K, V>.fromIterable constructor Null safety

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.

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;
}