Use Nimble to express the expected outcomes of Swift or Objective-C expressions. Inspired by Cedar.
After the announcement of Swift, ReactiveCocoa was rewritten in Swift. This framework creates a bridge between those Swift and Objective-C APIs (now known as ReactiveSwift and ReactiveObjC respectively).
Because the APIs are based on fundamentally different designs, the conversion is not always one-to-one; however, every attempt has been made to faithfully translate the concepts between the two APIs (and languages).