Instance Method

contains(where:)

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

Declaration

func contains(where predicate: @escaping (Upstream.Output) -> Bool) -> Publishers.ContainsWhere<Publishers.Share<Upstream>>

Parameters

predicate

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.

Discussion

This operator consumes elements produced from the upstream publisher until the upstream publisher produces a matching element.

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