1 files changed, 48 insertions, 0 deletions
diff --git a/include/mbgl/actor/message.hpp b/include/mbgl/actor/message.hpp
new file mode 100644
index 0000000000..cf071d4933
--- /dev/null
+++ b/include/mbgl/actor/message.hpp
@@ -0,0 +1,48 @@
+#pragma once
+
+#include <utility>
+
+namespace mbgl {
+
+// A movable type-erasing function wrapper. This allows to store arbitrary invokable
+// things (like std::function<>, or the result of a movable-only std::bind()) in the queue.
+// Source: http://stackoverflow.com/a/29642072/331379
+class Message {
+public:
+    virtual ~Message() = default;
+    virtual void operator()() = 0;
+};
+
+template <class Object, class MemberFn, class ArgsTuple>
+class MessageImpl : public Message {
+public:
+    MessageImpl(Object& object_, MemberFn memberFn_, ArgsTuple argsTuple_)
+      : object(object_),
+        memberFn(memberFn_),
+        argsTuple(std::move(argsTuple_)) {
+    }
+
+    void operator()() override {
+        invoke(std::make_index_sequence<std::tuple_size<ArgsTuple>::value>());
+    }
+
+    template <std::size_t... I>
+    void invoke(std::index_sequence<I...>) {
+        (object.*memberFn)(std::move(std::get<I>(argsTuple))...);
+    }
+
+    Object& object;
+    MemberFn memberFn;
+    ArgsTuple argsTuple;
+};
+
+namespace actor {
+
+template <class Object, class MemberFn, class... Args>
+std::unique_ptr<Message> makeMessage(Object& object, MemberFn memberFn, Args&&... args) {
+    auto tuple = std::make_tuple(std::forward<Args>(args)...);
+    return std::make_unique<MessageImpl<Object, MemberFn, decltype(tuple)>>(object, memberFn, std::move(tuple));
+}
+
+} // namespace actor
+} // namespace mbgl