Send cancellable actions from ActionDispatcher.

Sources/SwiftDux/Action/ActionDispatcher.swift

@@ -33,8 +33,16 @@ public protocol ActionDispatcher {
 
 extension ActionDispatcher {
 
+  /// Sends an action to a reducer to mutate the state of the application.
+  /// - Parameter action: An action to dispatch to the store.
   public func callAsFunction(_ action: Action) {
     send(action)
   }
-
+
+  /// Send an action that returns a cancellable object.
+  /// - Parameter action: The action
+  /// - Returns: A cancellable to cancel the action.
+  public func sendAsCancellable(_ action: CancellableAction) -> AnyCancellable {
+    action.sendAsCancellable(self)
+  }
 }

Sources/SwiftDux/Action/ActionPlan.swift

@@ -121,7 +121,7 @@ public struct ActionPlan<State>: CancellableAction where State: StateType {
   ///
   /// - Parameter send: The send function that dispatches an action.
   /// - Returns: AnyCancellable to cancel the action plan.
-  public func sendAsCancellable(_ send: ActionDispatcher) -> Cancellable {
+  public func sendAsCancellable(_ send: ActionDispatcher) -> AnyCancellable {
     var publisherCancellable: AnyCancellable? = nil
     send(
       ActionPlan<State> { store, completed in
@@ -132,11 +132,7 @@ public struct ActionPlan<State>: CancellableAction where State: StateType {
         return publisherCancellable
       }
     )
-
-    return AnyCancellable {
-      publisherCancellable?.cancel()
-      publisherCancellable = nil
-    }
+    return AnyCancellable { [publisherCancellable] in publisherCancellable?.cancel() }
   }
 
   /// Dispatches another action plan after this one has completed. This allows

Sources/SwiftDux/Action/CancellableAction.swift

@@ -38,6 +38,5 @@ public protocol CancellableAction: Action {
   ///
   /// - Parameter send: The send function that dispatches an action.
   /// - Returns: AnyCancellable to cancel the action plan.
-  func sendAsCancellable(_ send: ActionDispatcher) -> Cancellable
-
+  func sendAsCancellable(_ send: ActionDispatcher) -> AnyCancellable
 }