Remove old Effect.fireAndForget() (#430)

* Update Effect.swift

* Update Effect.swift

* Update Effect.swift

Author: stephencelis

Sources/ComposableArchitecture/Effect.swift

@@ -280,26 +280,6 @@ extension Effect where Failure == Swift.Error {
   }
 }
 
-extension Effect where Output == Never {
-  /// Upcasts an `Effect<Never, Failure>` to an `Effect<T, Failure>` for any type `T`. This is
-  /// possible to do because an `Effect<Never, Failure>` can never produce any values to feed back
-  /// into the store (hence the name "fire and forget"), and therefore we can act like it's an
-  /// effect that produces values of any type (since it never produces values).
-  ///
-  /// This is useful for times you have an `Effect<Never, Failure>` but need to massage it into
-  /// another type in order to return it from a reducer:
-  ///
-  ///     case .buttonTapped:
-  ///       return analyticsClient.track("Button Tapped")
-  ///         .fireAndForget()
-  ///
-  /// - Returns: An effect.
-  public func fireAndForget<T>() -> Effect<T, Failure> {
-    func absurd<A>(_ never: Never) -> A {}
-    return self.map(absurd)
-  }
-}
-
 extension Publisher {
   /// Turns any publisher into an `Effect`.
   ///
@@ -338,14 +318,20 @@ extension Publisher {
   /// and any failure.
   ///
   /// This is useful for times you want to fire off an effect but don't want to feed any data back
-  /// into the system.
+  /// into the system. It can automatically promote an effect to your reducer's domain.
   ///
   ///     case .buttonTapped:
   ///       return analyticsClient.track("Button Tapped")
   ///         .fireAndForget()
   ///
+  /// - Parameters:
+  ///   - outputType: An output type.
+  ///   - failureType: A failure type.
   /// - Returns: An effect that never produces output or errors.
-  public func fireAndForget<NewOutput, NewFailure>() -> Effect<NewOutput, NewFailure> {
+  public func fireAndForget<NewOutput, NewFailure>(
+    outputType: NewOutput.Type = NewOutput.self,
+    failureType: NewFailure.Type = NewFailure.self
+  ) -> Effect<NewOutput, NewFailure> {
     return
       self
       .flatMap { _ in Empty() }