union method

Iterable<T> union(
  1. Iterable<T> other
)

Returns a new lazy Iterable that represents the union of this iterable and the other iterable.

The returned Iterable lazily yields unique elements from both iterables. It uses a HashSet to track existing elements and ensure each element is yielded only once, effectively removing duplicates.

  • Parameters:

    • other: The iterable to be combined with this iterable.

  • Returns: A new lazy Iterable containing the unique elements from both this iterable and the other iterable.

  • Examples:

    List<int> firstList = [1, 2, 3];
List<int> secondList = [2, 3, 4];
Iterable<int> unionSet = firstList.union(secondList);
print(unionSet.toList()); // [1, 2, 3, 4]

Note: The function does not preserve the order of elements. Elements are yielded in the order they are encountered without duplicates.

Implementation

Iterable<T> union(Iterable<T> other) sync* {
  var existing = HashSet<T>();
  for (var element in this) {
    if (existing.add(element)) yield element;
  }

  for (var element in other) {
    if (existing.add(element)) yield element;
  }
}