What is the role and main applications of the Combine and RxSwift libraries in reactive application development?

Combine and RxSwift are libraries for reactive programming in iOS that help work with asynchronous data streams and events.

Main roles and applications:

• Managing Asynchrony: allow subscribing to data streams (e.g., user input, network requests) and reacting to changes.
• Data Composition and Transformation: provide operators for filtering, transforming, and combining events.
• Simplifying Architecture: help build cleaner and more declarative code, reducing callbacks and complex states.

Example with Combine:

import Combine

let publisher = Just(5)
let subscription = publisher
    .map { $0 * 2 }
    .sink { value in
        print("Received value: \(value)")
    }

Here, a stream with a single value is created, transformed, and the subscriber receives the result.