OR-5269 Operators:: Sequence Operators:: Finding values:: last(where:)

[crazymanish]

Context

• Close ticket: [w25(18june-24june)] Operators:: Sequence Operators: Finding values #32

Operators are publishers

• In Combine, methods that perform an operation on values coming from a publisher are called operators.
• Each Combine operator actually returns a publisher. Generally speaking, that publisher receives the upstream values, manipulates the data, and then sends that data downstream.

Sequence operators

• Sequence operators are easiest to understand when you realize that publishers are just sequences themselves.
• Sequence operators work with the collection of a publisher’s values, much like an array or set — which, of course, are just finite sequences!

Finding values

• This file consists of operators that locate specific values the publisher emits based on different criteria.
• These are similar to the collection methods in the Swift standard library.

In this PR

• Operators:: Sequence Operators:: Finding values:: last(where:)
• last(where:) Publishes the last element of a stream that satisfies a predicate closure, after upstream finishes.
• A closure that takes an element as its parameter and returns a Boolean value that indicates whether to publish the element.
• https://developer.apple.com/documentation/combine/publishers/reduce/last(where:)