New move support for strand. Note that some copies are unavoidable.

asio/include/asio/detail/wrapped_handler.hpp

@@ -36,6 +36,20 @@ public:
   {
   }
 
+#if defined(ASIO_HAS_MOVE)
+  wrapped_handler(const wrapped_handler& other)
+    : dispatcher_(other.dispatcher_),
+      handler_(other.handler_)
+  {
+  }
+
+  wrapped_handler(wrapped_handler&& other)
+    : dispatcher_(other.dispatcher_),
+      handler_(ASIO_MOVE_CAST(Handler)(other.handler_))
+  {
+  }
+#endif // defined(ASIO_HAS_MOVE)
+
   void operator()()
   {
     dispatcher_.dispatch(handler_);
@@ -125,12 +139,32 @@ template <typename Handler, typename Context>
 class rewrapped_handler
 {
 public:
-  explicit rewrapped_handler(const Handler& handler, const Context& context)
-    : handler_(handler),
-      context_(context)
+  explicit rewrapped_handler(Handler& handler, const Context& context)
+    : context_(context),
+      handler_(ASIO_MOVE_CAST(Handler)(handler))
   {
   }
 
+  explicit rewrapped_handler(const Handler& handler, const Context& context)
+    : context_(context),
+      handler_(handler)
+  {
+  }
+
+#if defined(ASIO_HAS_MOVE)
+  rewrapped_handler(const rewrapped_handler& other)
+    : context_(other.context_),
+      handler_(other.handler_)
+  {
+  }
+
+  rewrapped_handler(rewrapped_handler&& other)
+    : context_(ASIO_MOVE_CAST(Context)(other.context_)),
+      handler_(ASIO_MOVE_CAST(Handler)(other.handler_))
+  {
+  }
+#endif // defined(ASIO_HAS_MOVE)
+
   void operator()()
   {
     handler_();
@@ -142,8 +176,8 @@ public:
   }
 
 //private:
-  Handler handler_;
   Context context_;
+  Handler handler_;
 };
 
 template <typename Dispatcher, typename Handler>
@@ -162,6 +196,15 @@ inline void asio_handler_deallocate(void* pointer, std::size_t size,
       pointer, size, this_handler->handler_);
 }
 
+template <typename Function, typename Dispatcher, typename Handler>
+inline void asio_handler_invoke(Function& function,
+    wrapped_handler<Dispatcher, Handler>* this_handler)
+{
+  this_handler->dispatcher_.dispatch(
+      rewrapped_handler<Function, Handler>(
+        function, this_handler->handler_));
+}
+
 template <typename Function, typename Dispatcher, typename Handler>
 inline void asio_handler_invoke(const Function& function,
     wrapped_handler<Dispatcher, Handler>* this_handler)
@@ -187,6 +230,14 @@ inline void asio_handler_deallocate(void* pointer, std::size_t size,
       pointer, size, this_handler->context_);
 }
 
+template <typename Function, typename Handler, typename Context>
+inline void asio_handler_invoke(Function& function,
+    rewrapped_handler<Handler, Context>* this_handler)
+{
+  asio_handler_invoke_helpers::invoke(
+      function, this_handler->context_);
+}
+
 template <typename Function, typename Handler, typename Context>
 inline void asio_handler_invoke(const Function& function,
     rewrapped_handler<Handler, Context>* this_handler)

asio/include/asio/strand.hpp

@@ -140,13 +140,13 @@ public:
    * @code void handler(); @endcode
    */
   template <typename CompletionHandler>
-  void dispatch(CompletionHandler handler)
+  void dispatch(ASIO_MOVE_ARG(CompletionHandler) handler)
   {
     // If you get an error on the following line it means that your handler does
     // not meet the documented type requirements for a CompletionHandler.
     ASIO_COMPLETION_HANDLER_CHECK(CompletionHandler, handler) type_check;
 
-    service_.dispatch(impl_, handler);
+    service_.dispatch(impl_, ASIO_MOVE_CAST(CompletionHandler)(handler));
   }
 
   /// Request the strand to invoke the given handler and return
@@ -166,13 +166,13 @@ public:
    * @code void handler(); @endcode
    */
   template <typename CompletionHandler>
-  void post(CompletionHandler handler)
+  void post(ASIO_MOVE_ARG(CompletionHandler) handler)
   {
     // If you get an error on the following line it means that your handler does
     // not meet the documented type requirements for a CompletionHandler.
     ASIO_COMPLETION_HANDLER_CHECK(CompletionHandler, handler) type_check;
 
-    service_.post(impl_, handler);
+    service_.post(impl_, ASIO_MOVE_CAST(CompletionHandler)(handler));
   }
 
   /// Create a new handler that automatically dispatches the wrapped handler