Combine

• Swift Stuff https://www.youtube.com/watch?v=0wTld_ROx2Y&feature=emb_title

https://speakerdeck.com/shiz/sorosorocombine

• “Declarative API for handling various types of asynchronous processing in a single method”

  • Various types: delegate, closure, etc..
    • All of these become Publishers
  • Declarative: Specify only the purpose?

• One of the advantages of Combine is that it can be optimized internally.

• Publisher<Output, Failure: Error>

  • Continues to emit values: Output until Completion (either finished or failure) occurs.

• Subscriber<Input, Failure: Error>

  • Receives values from the Publisher (Input and Output, Failure and Failure values must be the same)
  • Receiver-driven, the Subscriber only receives the necessary amount of values (known as BackPressure)
    • Adjusts demand

• Subscription

  • Mediates between Publisher and Subscriber
  • Cancellable
    • AnyCancellable: Automatically cancels when released from memory
      • Useful for cases like removing previous processes during screen transitions #iOSDC2020