Instance Method


Publishes a Boolean value upon receiving an element that satisfies the throwing predicate closure.


func tryContains(where predicate: @escaping (Upstream.Output) throws -> Bool) -> Publishers.TryContainsWhere<Publishers.Share<Upstream>>



A closure that takes an element as its parameter and returns a Boolean value indicating whether the element satisfies the closure’s comparison logic.

Return Value

A publisher that emits the Boolean value true when the upstream publisher emits a matching value.


This operator consumes elements produced from the upstream publisher until the upstream publisher produces a matching element. If the closure throws, the stream fails with an error.

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