nub method

Queue<E> nub({
  1. Iterable<E>? elementsToNub,
  2. bool equalityFunction(
    1. E a,
    2. E b
    ) = h.symmetricDeepEquals,
})

Removes duplicates.

1, 1, 2, 2, 3, 3.nub() returns 1, 2, 3.

Optional parameter means .nub() will only apply to those elements:

1, 1, 1, 2, 2, 2, 3, 3, 3.nub(2, 3) returns 1, 1, 1, 2, 3.

Empty argument has no effect: 1, 1, 2, 2, 3, 3.nub([]) returns 1, 1, 2, 2, 3, 3.

Nested lists: [1,2, 1,2].nub() returns [1,2].

Default h.symmetricDeepEquals checks DeepCollectionEquality().equals in both directions since it is asymmetric, but equalityFunction allows a custom function to be used instead. For asymmetric equality functions, elements are compared left to right.

Implementation

Queue<E> nub({
  Iterable<E>? elementsToNub,
  bool Function(E a, E b) equalityFunction = h.symmetricDeepEquals,
}) {
  return h
      .nubIterable(
        original: this,
        elementsToNub: elementsToNub,
        equalityFunction: equalityFunction,
      )
      .toQueue();
}