add SlotGuard

include/td/misc/Signal.h

@@ -10,15 +10,16 @@ namespace utils {
 
 template <typename... Args>
 class Signal : private NonCopyable {
-  private:
+  public:
 	using FnType = void(Args...);
 	using CallBack = std::function<FnType>;
 
+  private:
 	std::vector<CallBack> m_Callbacks;
 
   public:
-	void Connect(CallBack&& a_Callback) {
+	void Connect(const CallBack& a_Callback) {
-		m_Callbacks.push_back(std::move(a_Callback));
+		m_Callbacks.push_back(a_Callback);
 	}
 
 	void Disconnect(const CallBack& a_Callback) {

include/td/misc/SlotGuard.h

@@ -0,0 +1,27 @@
+#pragma once
+
+#include <td/misc/SlotGuard.h>
+
+namespace td {
+namespace utils {
+
+class SlotGuard {
+  private:
+	std::vector<std::function<void()>> m_Deleters;
+
+  public:
+	template <typename... Args>
+	void Connect(Signal<Args...>& a_Signal, const typename Signal<Args...>::CallBack& a_Callback) {
+		a_Signal.Connect(a_Callback);
+		m_Deleters.push_back([&a_Signal, &a_Callback]() { a_Signal.Disconnect(a_Callback); });
+	}
+
+	~SlotGuard() {
+		for (auto& deleter : m_Deleters) {
+			deleter();
+		}
+	}
+};
+
+}  // namespace utils
+}  // namespace td