Rx\Observable::distinctUntilChanged PHP Method

distinctUntilChanged() public method

A variant of distinct that only compares emitted items from the source Observable against their immediate predecessors in order to determine whether or not they are distinct.
public distinctUntilChanged ( callable $comparer = null ) : Rx\Observable\AnonymousObservable
$comparer callable
return Rx\Observable\AnonymousObservable
    public function distinctUntilChanged(callable $comparer = null)
    {
        return $this->lift(function () use($comparer) {
            return new DistinctUntilChangedOperator(null, $comparer);
        });
    }