Prototype event-loop.h for queue dependency injection.
Change-Id: I1af3f71a5b0cca741641f872f55dab10474ee064
diff --git a/aos/events/event-loop-tmpl.h b/aos/events/event-loop-tmpl.h
new file mode 100644
index 0000000..4c53be3
--- /dev/null
+++ b/aos/events/event-loop-tmpl.h
@@ -0,0 +1,40 @@
+#ifndef _AOS_EVENTS_EVENT_LOOP_TMPL_H_
+#define _AOS_EVENTS_EVENT_LOOP_TMPL_H_
+
+#include <type_traits>
+#include "aos/events/event-loop.h"
+
+namespace aos {
+
+// From a watch functor, this will extract the message type of the argument.
+// This is the template forward declaration, and it extracts the call operator
+// as a PTMF to be used by the following specialization.
+template <class T>
+struct watch_message_type_trait
+ : watch_message_type_trait<decltype(&T::operator())> {};
+
+// From a watch functor, this will extract the message type of the argument.
+// This is the template specialization.
+template <class ClassType, class ReturnType, class A1>
+struct watch_message_type_trait<ReturnType (ClassType::*)(A1) const> {
+ using message_type = typename std::decay<A1>::type;
+};
+
+template <typename T>
+typename Sender<T>::Message Sender<T>::MakeMessage() {
+ return Message(sender_.get());
+}
+
+template <typename Watch>
+void EventLoop::MakeWatcher(const std::string &path, Watch &&w) {
+ using T = typename watch_message_type_trait<Watch>::message_type;
+
+ return MakeRawWatcher(path, QueueTypeInfo::Get<T>(),
+ [w](const Message *message) {
+ w(*reinterpret_cast<const T *>(message));
+ });
+}
+
+} // namespace aos
+
+#endif // _AOS_EVENTS_EVENT_LOOP_TMPL_H