Generic typealias Signal.Event.Transformation.

Author: andersio

Sources/Event.swift

@@ -180,7 +180,9 @@ extension Signal.Event: EventProtocol {
 }
 
 extension Signal.Event {
-	internal static func filter(_ isIncluded: @escaping (Value) -> Bool) -> (@escaping Signal<Value, Error>.Observer.Action) -> (Signal<Value, Error>.Event) -> Void {
+	internal typealias Transformation<U, E: Swift.Error> = (@escaping Signal<U, E>.Observer.Action) -> (Signal<Value, Error>.Event) -> Void
+
+	internal static func filter(_ isIncluded: @escaping (Value) -> Bool) -> Transformation<Value, Error> {
 		return { action in
 			return { event in
 				switch event {
@@ -202,7 +204,7 @@ extension Signal.Event {
 		}
 	}
 
-	internal static func filterMap<U>(_ transform: @escaping (Value) -> U?) -> (@escaping Signal<U, Error>.Observer.Action) -> (Signal<Value, Error>.Event) -> Void {
+	internal static func filterMap<U>(_ transform: @escaping (Value) -> U?) -> Transformation<U, Error> {
 		return { action in
 			return { event in
 				switch event {
@@ -224,7 +226,7 @@ extension Signal.Event {
 		}
 	}
 
-	internal static func map<U>(_ transform: @escaping (Value) -> U) -> (@escaping Signal<U, Error>.Observer.Action) -> (Signal<Value, Error>.Event) -> Void {
+	internal static func map<U>(_ transform: @escaping (Value) -> U) -> Transformation<U, Error> {
 		return { action in
 			return { event in
 				switch event {
@@ -244,7 +246,7 @@ extension Signal.Event {
 		}
 	}
 
-	internal static func mapError<E>(_ transform: @escaping (Error) -> E) -> (@escaping Signal<Value, E>.Observer.Action) -> (Signal<Value, Error>.Event) -> Void {
+	internal static func mapError<E>(_ transform: @escaping (Error) -> E) -> Transformation<Value, E> {
 		return { action in
 			return { event in
 				switch event {
@@ -264,7 +266,7 @@ extension Signal.Event {
 		}
 	}
 
-	internal static func take(first count: Int) -> (@escaping Signal<Value, Error>.Observer.Action) -> (Signal<Value, Error>.Event) -> Void {
+	internal static func take(first count: Int) -> Transformation<Value, Error> {
 		assert(count >= 1)
 
 		return { action in

Sources/Observer.swift

@@ -35,7 +35,7 @@ extension Signal {
 		///                 upstream.
 		internal init<U, E: Swift.Error>(
 			_ observer: Signal<U, E>.Observer,
-			_ transform: @escaping (@escaping Signal<U, E>.Observer.Action) -> Action,
+			_ transform: @escaping Event.Transformation<U, E>,
 			_ disposable: Disposable
 		) {
 			var hasDeliveredTerminalEvent = false

Sources/Signal.swift

@@ -537,7 +537,7 @@ extension Signal {
 	///                closure.
 	///
 	/// - returns: A signal that forwards events yielded by the action.
-	internal func flatMapEvent<U, E>(_ transform: @escaping (@escaping Signal<U, E>.Observer.Action) -> (Event) -> Void) -> Signal<U, E> {
+	internal func flatMapEvent<U, E>(_ transform: @escaping Event.Transformation<U, E>) -> Signal<U, E> {
 		return Signal<U, E> { observer in
 			return self.observe(.init(observer, transform, NopDisposable.shared))
 		}

Sources/SignalProducer.swift

@@ -272,7 +272,7 @@ internal class SignalProducerCore<Value, Error: Swift.Error> {
 	///                closure.
 	///
 	/// - returns: A producer that forwards events yielded by the action.
-	internal func flatMapEvent<U, E>(_ transform: @escaping (@escaping Signal<U, E>.Observer.Action) -> (Signal<Value, Error>.Event) -> Void) -> SignalProducer<U, E> {
+	internal func flatMapEvent<U, E>(_ transform: @escaping Signal<Value, Error>.Event.Transformation<U, E>) -> SignalProducer<U, E> {
 		return SignalProducer<U, E>(TransformerCore(source: self, transform: transform))
 	}
 }
@@ -316,9 +316,9 @@ private final class SignalCore<Value, Error: Swift.Error>: SignalProducerCore<Va
 /// - note: This core does not use `Signal` unless it is requested via `makeInstance()`.
 private final class TransformerCore<Value, Error: Swift.Error, SourceValue, SourceError: Swift.Error>: SignalProducerCore<Value, Error> {
 	private let source: SignalProducerCore<SourceValue, SourceError>
-	private let transform: (@escaping Signal<Value, Error>.Observer.Action) -> (Signal<SourceValue, SourceError>.Event) -> Void
+	private let transform: Signal<SourceValue, SourceError>.Event.Transformation<Value, Error>
 
-	init(source: SignalProducerCore<SourceValue, SourceError>, transform: @escaping (@escaping Signal<Value, Error>.Observer.Action) -> (Signal<SourceValue, SourceError>.Event) -> Void) {
+	init(source: SignalProducerCore<SourceValue, SourceError>, transform: @escaping Signal<SourceValue, SourceError>.Event.Transformation<Value, Error>) {
 		self.source = source
 		self.transform = transform
 	}
@@ -327,7 +327,7 @@ private final class TransformerCore<Value, Error: Swift.Error, SourceValue, Sour
 		return source.start { Signal.Observer(generator($0), transform, $0) }
 	}
 
-	internal override func flatMapEvent<U, E>(_ transform: @escaping (@escaping Signal<U, E>.Observer.Action) -> (Signal<Value, Error>.Event) -> Void) -> SignalProducer<U, E> {
+	internal override func flatMapEvent<U, E>(_ transform: @escaping Signal<Value, Error>.Event.Transformation<U, E>) -> SignalProducer<U, E> {
 		return SignalProducer<U, E>(TransformerCore<U, E, SourceValue, SourceError>(source: source) { [innerTransform = self.transform] action in
 			return innerTransform(transform(action))
 		})