add reenterafter overloads (#1671)

src/Proto.Actor/Context/ActorContext.cs

@@ -231,6 +231,33 @@ public void ReenterAfter(Task target, Action action)
 
         ScheduleContinuation(target, cont);
     }
+
+    public void ReenterAfter(Task target, Action<Task> action)
+    {
+        var msg = _messageOrEnvelope;
+
+        var cont = new Continuation(
+            () => {
+                action(target);
+                return Task.CompletedTask;
+            },
+            msg,
+            Actor);
+
+        ScheduleContinuation(target, cont);
+    }
+
+    public void ReenterAfter(Task target, Func<Task,Task> action)
+    {
+        var msg = _messageOrEnvelope;
+
+        var cont = new Continuation(
+            () => action(target),
+            msg,
+            Actor);
+
+        ScheduleContinuation(target, cont);
+    }
 
     public Task Receive(MessageEnvelope envelope)
     {

src/Proto.Actor/Context/ActorContextDecorator.cs

@@ -72,6 +72,12 @@ public virtual void ReenterAfter<T>(Task<T> target, Func<Task<T>, Task> action)
     public virtual void ReenterAfter(Task target, Action action) =>
         _context.ReenterAfter(target, action);
 
+    public void ReenterAfter(Task target, Action<Task> action) => 
+        _context.ReenterAfter(target, action);
+
+    public void ReenterAfter(Task target, Func<Task, Task> action) =>
+        _context.ReenterAfter(target, action);
+
     public CapturedContext Capture() => _context.Capture();
 
     public void Apply(CapturedContext capturedContext) => _context.Apply(capturedContext);

src/Proto.Actor/Context/IContext.cs

@@ -90,6 +90,26 @@ public interface IContext : ISenderContext, IReceiverContext, ISpawnerContext, I
     /// <param name="target">the Task to await</param>
     /// <param name="action">the continuation to call once the task is completed</param>
     void ReenterAfter(Task target, Action action);
+
+    /// <summary>
+    ///     Awaits the given target task and once completed, the given action is then completed within the actors concurrency
+    ///     constraint.
+    ///     The concept is called Reentrancy, where an actor can continue to process messages while also awaiting that some
+    ///     asynchronous operation completes.
+    /// </summary>
+    /// <param name="target">the Task to await</param>
+    /// <param name="action">the continuation to call once the task is completed</param>
+    void ReenterAfter(Task target, Action<Task> action);
+
+    /// <summary>
+    ///     Awaits the given target task and once completed, the given action is then completed within the actors concurrency
+    ///     constraint.
+    ///     The concept is called Reentrancy, where an actor can continue to process messages while also awaiting that some
+    ///     asynchronous operation completes.
+    /// </summary>
+    /// <param name="target">the Task to await</param>
+    /// <param name="action">the continuation to call once the task is completed</param>
+    void ReenterAfter(Task target, Func<Task,Task> action);
 
     /// <summary>
     /// Captures the current MessageOrEnvelope for the ActorContext