Callbag

This is an implemented Callbag protocol founded by André Staltz in Swift.

Specification

  Talkback  = (_ payload:Any?) -> Void
  Sink<T>   = (_ payload:Payload<T>) -> Void
  Source<T> = (_ sink:Sink<T>) -> Void;

Functions have been implemented

Factories

• fromArray
• fromInterval
• fromSubject
• makeReplaySubject
• makeSubject
• create
• empty
• never

Sink factories

• subscribe

Operators

• map
• flatmap
• filter
• take
• first
• skip
• last
• scan
• merge
• combine

Example

To run the example project, clone the repo, and run pod install from the Example directory first.

Reactive programming examples

Pick the first 5 odd numbers from a clock that ticks every second, then start observing them:

   fromInterval(1)
      => map{ $0 + 1}
      => filter{ $0 % 2 != 0}
      => take(5)
      => forEach{ print($0)}
   //1
   //3
   //5
   //7
   //9

From a array

    fromArray([1,2,3,4,5,6,7,8,9]) // 1, 2, 3, 4, 5, 6, 7, 8, 9,
       => filter{ $0 % 2 == 0}    // 2, 4, 6, 8
       => map { $0 * 2}           // 4, 8, 12, 16
       => subscribe{ print($0)}
        
    //4
    //8
    //12
    //16

Installation

Callbag is available through CocoaPods. To install it, simply add the following line to your Podfile:

pod 'Callbag'

References

• https://staltz.com/why-we-need-callbags.html
• http://blog.krawaller.se/posts/callbags-introduction/
• http://blog.krawaller.se/posts/explaining-callbags-via-typescript-definitions/
• https://wonka.kitten.sh/
• https://github.com/callbag/callbag/wiki