# addAll method

1. @override

void addAll(

1. Iterable<E> elements

)
override

Adds all `elements` to this set.

Equivalent to adding each element in `elements` using add, but some collections may be able to optimize it.

    final characters = <String>{'A', 'B'};
    characters.addAll({'A', 'B', 'C'});
    print(characters); // {A, B, C}

## Implementation

    @override
    void addAll(Iterable<E> elements) {
      for (final element in elements) {
        add(element);
      }
    }