retainWhere method Null safety

void retainWhere(
  1. bool test(
    1. E element
    )
)
override

Removes all elements of this set that fail to satisfy test.

Implementation

void retainWhere(bool test(E element)) {
  List<Object?> toRemove = [];
  for (E element in this) {
    if (!test(element)) toRemove.add(element);
  }
  removeAll(toRemove);
}