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No Maintenance Intended

⚠️ Deprecated ⚠️

This repo is no longer being maintained. It has been supersede by:

  1. ReactiveSwift: for core operators.
  2. ReactiveCocoa: for UI operators.

Some operators have not been ported. If something is amiss, please open a PR, or an issue, in the corresponding repo. ❤️


Rex Carthage compatible

Extensions for ReactiveCocoa that may not fit in the core framework.

New development targets RAC 4/Swift 2/Xcode 7. For RAC 3 support see the 0.5 release.


All Signal operators are available for SignaProducers too via explicit lifting.


Applies transform to values from signal with non-nil results unwrapped and forwared on the returned signal. This is equivalent to map { … } .filter { $0 != nil } .map { $0! } but without creating extra intermediate signals.

func filterMap<U>(transform: T -> U?) -> Signal<U, E>

Wraps a signal in a version that drops Error events. By default errors are replaced with a Completed event but Interrupted can also be specified as replacement.

func ignoreError(#replacement: Event<T, NoError> = .Completed) -> Signal<T, NoError>

Forwards events from signal until it terminates or until interval time passes. This is nearly identical to timeoutWithError from RAC except any terminating event can be used for the timeout.

func timeoutAfter(interval: NSTimeInterval, withEvent event: Event<T, E>, onScheduler scheduler: DateSchedulerType) -> Signal<T, E>

Flattens batches of elements sent on signal into each individual element. The inverse of collect. Requires signal values to conform to SequenceType.

func uncollect() -> Signal<T.Generator.Element, E>


Operators specific to SignalProducer.


Partitions values from producer into new producer groups based on the key returned from grouping. Termination events on the original producer are forwarded to each inner producer group.

func groupBy<K: Hashable>(grouping: T -> K) -> SignalProducer<(K, SignalProducer<T, E>), E>

UIKit Extensions


Flexible way to bind CocoaAction to the press of button. In addition the button will be disabled during the Action executing. Such behavior is convenient for tasks that require some time, like a download process in the example below.

let downloadAction = Action<UIButton, NSData, NSError> { _ in
    let url = NSURL(string: "")
    let request = NSURLRequest(URL: url!)
    return NSURLSession.sharedSession().rac_dataWithRequest(request).map { $0.0 }

downloadButton.rex_pressed.value = downloadAction.unsafeCocoaAction


Rex is released under the MIT license