Add merge(with:) operator

CHANGELOG.md

@@ -1,6 +1,8 @@
 # master
 *Please add new entries at the top.*
 
+1. New operator `merge(with:)` (#600, kudos to @ra1028)
+
 # 3.1.0
 1. Fixed `schedule(after:interval:leeway:)` being cancelled when the returned `Disposable` is not retained. (#584, kudos to @jjoelson)
 

Sources/Flatten.swift

@@ -481,46 +481,32 @@ extension UnsafeAtomicState where State == ProducerState {
 }
 
 extension Signal {
-	/// Merges the given signals into a single `Signal` that will emit all
-	/// values from each of them, and complete when all of them have completed.
-	///
-	/// - parameters:
-	///   - signals: A sequence of signals to merge.
+	/// Merges the values of all the given signals, in the manner described
+	/// by `merge(with:)`.
 	public static func merge<Seq: Sequence>(_ signals: Seq) -> Signal<Value, Error> where Seq.Iterator.Element == Signal<Value, Error>
 	{
 		return SignalProducer<Signal<Value, Error>, Error>(signals)
 			.flatten(.merge)
 			.startAndRetrieveSignal()
 	}
 
-	/// Merges the given signals into a single `Signal` that will emit all
-	/// values from each of them, and complete when all of them have completed.
-	///
-	/// - parameters:
-    ///   - signals: A list of signals to merge.
+	/// Merges the values of all the given signals, in the manner described
+	/// by `merge(with:)`.
 	public static func merge(_ signals: Signal<Value, Error>...) -> Signal<Value, Error> {
 		return Signal.merge(signals)
 	}
 }
 
 extension SignalProducer {
-	/// Merges the given producers into a single `SignalProducer` that will emit
-	/// all values from each of them, and complete when all of them have
-	/// completed.
-	///
-	/// - parameters:
-	///   - producers: A sequence of producers to merge.
+	/// Merges the values of all the given producers, in the manner described
+	/// by `merge(with:)`.
 	public static func merge<Seq: Sequence>(_ producers: Seq) -> SignalProducer<Value, Error> where Seq.Iterator.Element == SignalProducer<Value, Error>
 	{
 		return SignalProducer<Seq.Iterator.Element, NoError>(producers).flatten(.merge)
 	}
 
-	/// Merges the given producers into a single `SignalProducer` that will emit
-	/// all values from each of them, and complete when all of them have
-	/// completed.
-	///
-	/// - parameters:
-	///   - producers: A sequence of producers to merge.
+	/// Merges the values of all the given producers, in the manner described
+	/// by `merge(with:)`.
 	public static func merge(_ producers: SignalProducer<Value, Error>...) -> SignalProducer<Value, Error> {
 		return SignalProducer.merge(producers)
 	}

Sources/Signal.swift

@@ -788,6 +788,17 @@ extension Signal {
 	public func combineLatest<U>(with other: Signal<U, Error>) -> Signal<(Value, U), Error> {
 		return Signal.combineLatest(self, other)
 	}
+
+	/// Merge the given signal into a single `Signal` that will emit all
+	/// values from both of them, and complete when all of them have completed.
+	///
+	/// - parameters:
+	///   - other: A signal to merge `self`'s value with.
+	///
+	/// - returns: A signal that sends all values of `self` and given signal.
+	public func merge(with other: Signal<Value, Error>) -> Signal<Value, Error> {
+		return Signal.merge(self, other)
+	}
 
 	/// Delay `value` and `completed` events by the given interval, forwarding
 	/// them on the given scheduler.

Sources/SignalProducer.swift

@@ -1076,6 +1076,17 @@ extension SignalProducer {
 	public func combineLatest<Other: SignalProducerConvertible>(with other: Other) -> SignalProducer<(Value, Other.Value), Error> where Other.Error == Error {
 		return SignalProducer.combineLatest(self, other)
 	}
+
+	/// Merge the given producer into a single `SignalProducer` that will emit all
+	/// values from both of them, and complete when all of them have completed.
+	///
+	/// - parameters:
+	///   - other: A producer to merge `self`'s value with.
+	///
+	/// - returns: A producer that sends all values of `self` and given producer.
+	public func merge(with other: SignalProducer<Value, Error>) -> SignalProducer<Value, Error> {
+		return SignalProducer.merge(self, other)
+	}
 
 	/// Delay `value` and `completed` events by the given interval, forwarding
 	/// them on the given scheduler.