Implement support for connecting void-args functions on Events. The use case is to shorten the function signature in cases where the user does not care about the event arguments.

# Conflicts:
#	include/Event.h
#	main.cpp

CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.27)
+cmake_minimum_required(VERSION 3.18..3.27)
 project(Event
     VERSION 1.0
     LANGUAGES CXX

include/Event.h

@@ -1,8 +1,8 @@
-/// @file        BasicEvent.hpp
-/// @description Templated BasicEvent Hook Class modeled after C# events
+/// @file        Connection.hpp
+/// @description Callback handler for event connections
 /// @author      Josh O'Leary - Redacted Software
 /// @revision    3
-/// @lastedit    2024-06-01
+/// @lastedit    2024-02-21
 /// @license     Unlicense - Public Domain
 
 #pragma once
@@ -11,45 +11,54 @@
 #include <functional>
 #include <memory>
 
-// TODO: ThreadSafeEvent / AsyncEvent version of the class.
-// TODO: ConsumableEvent - a version that can be "consumed" by a callback by returning true. It will be sunk and not passed to further callbacks.
-
-/// See EventConnection.h
+/// A delegate can be any function object or function-like object. The Args are the arguments accepted by that object
 template <typename delegate, typename ... Args>
-class Connection;
-
-/// @see Event.h
-template <typename delegate, typename ... Args>
-class BasicEvent;
-
-/// A type that represents a handle to an active event connection.
-template <typename delegate, typename ... Args>
-class Connection {
-public:
-    friend BasicEvent<delegate, Args...>;
+class BasicEvent {
 public:
+    /// A type that represents a handle to an active event connection.
+    class Connection {
+    public:
         Connection(BasicEvent<delegate, Args...> *creator, delegate cb);
         bool Disconnect(); // Breaks the event connection, but does not destroy the instance
+        // If improperly used could lead to run away events? - Maxine
         void Invoke(Args... e);
-public:
-    // Fuck it make this public
-    // Don't be stupid!!
+    public:
+        // This is made public in the case of function-like objects which store extra data.
+        // This allows us to access members of the object when desired. See JTest's usage of the event system for an example.
         delegate callback;
-private:
-    BasicEvent<delegate, Args...> * owner;
-    //delegate callback;
+    private:
+        BasicEvent<delegate, Args...> *owner;
         bool active = true;
+    };
+
+    using EventPtr = std::shared_ptr<Connection>;
+public:
+    // See JTest Unit for why making this virtual is convenient
+    virtual void Invoke(Args... args);
+    void operator()(Args... args);
+    Connection Connect(delegate callback);
+    void Disconnect(Connection &conn);
+    Connection operator+=(delegate callback);
+
+    /// Also support binding callbacks that don't read in arguments, as a shorthand.
+    // TODO: No need to wrap the callback if the template args type is void.
+    Connection Connect(const std::function<void()>& default_callback);
+    /// Also support binding callbacks that don't read in arguments, as a shorthand.
+    // TODO: No need to wrap the callback if the template args type is void.
+    Connection operator += (const std::function<void()>& default_callback);
+
+protected:
+    std::vector<EventPtr> listeners;
 };
 
 template<typename delegate, typename... Args>
-Connection<delegate, Args...>::Connection(BasicEvent<delegate, Args...> *creator, delegate cb) : owner(creator), callback(std::move(cb)) {}
-
+BasicEvent<delegate, Args...>::Connection::Connection(BasicEvent<delegate, Args...> *creator, delegate cb) : owner(creator), callback(std::move(cb)) {}
 
 template <typename delegate, typename... Args>
-void Connection<delegate, Args...>::Invoke(Args... e) { callback(e...); }
+void BasicEvent<delegate, Args...>::Connection::Invoke(Args... e) { callback(e...); }
 
 template <typename delegate, typename ... Args>
-bool Connection<delegate, Args...>::Disconnect() {
+bool BasicEvent<delegate, Args...>::Connection::Disconnect() {
     if (active) {
         owner->Disconnect(this);
         active = false;
@@ -58,54 +67,45 @@ bool Connection<delegate, Args...>::Disconnect() {
     return false;
 }
 
-/// BasicEvent is a templated class that can be used to raise events that can be listened in on
-/// at other points in a codebase without having to tightly couple the two pieces of code.
-/// @param delegate A type that can be invoked via operator() 'Call operator'.
-/// @param Args... The arguments that will be expected by this event and passed to it's delegate.
-template <typename delegate, typename ... Args>
-class BasicEvent {
-public:
-    using connection = Connection<delegate, Args ...>;
-    using event_ptr = std::shared_ptr<connection>;
-public:
-    /// Invokes the event, calling all currently bound connections, and passing in the given arguments.
-    virtual void Invoke(Args... args);
-    /// The call operator also invokes the event
-    void operator()(Args... args);
-    connection Connect(delegate callback);
-    void Disconnect(connection &conn);
-    connection operator+=(delegate callback);
-protected:
-    std::vector<event_ptr> listeners;
-    //uint64_t listenerCounter = 0;
-};
+template<typename delegate, typename... Args>
+BasicEvent<delegate, Args...>::Connection BasicEvent<delegate, Args...>::operator+=(delegate callback) { return Connect(callback); }
+
+template<typename delegate, typename ... Args>
+typename BasicEvent<delegate, Args...>::Connection BasicEvent<delegate, Args...>::Connect(
+    const std::function<void()> &default_callback) {
+    delegate wrapper = [default_callback] (Args... args) { default_callback(); };
+    return Connect(wrapper);
+}
+
+template<typename delegate, typename ... Args>
+typename BasicEvent<delegate, Args...>::Connection BasicEvent<delegate, Args...>::operator+=(
+    const std::function<void()> &default_callback) {
+    return Connect(default_callback);
+}
 
 template<typename delegate, typename... Args>
-Connection<delegate, Args...> BasicEvent<delegate, Args...>::operator+=(delegate callback) { return Connect(callback); }
-
-template<typename delegate, typename... Args>
-void BasicEvent<delegate, Args...>::operator()(Args... args) { Invoke(args...);}
+void BasicEvent<delegate, Args...>::operator()(Args... args) { Invoke(args...); }
 
 template <typename delegate, typename ... Args>
 void BasicEvent<delegate, Args...>::Invoke(Args... args) {
-    for (event_ptr &connection_ptr: this->listeners)
+    for (EventPtr &connection_ptr: this->listeners) {
         connection_ptr->Invoke(args...);
+    }
 }
 
 template <typename delegate, typename ... Args>
-Connection<delegate, Args...>  BasicEvent<delegate, Args...>::Connect(delegate callback)
-{
-    event_ptr retval(new connection(this, callback));
+BasicEvent<delegate, Args...>::Connection BasicEvent<delegate, Args...>::Connect(delegate callback) {
+    EventPtr retval(new Connection(this, callback));
     this->listeners.push_back(retval);
     return *retval;
 }
 
 template <typename delegate, typename ... Args>
-void BasicEvent<delegate, Args...>::Disconnect(connection &conn) {
+void BasicEvent<delegate, Args...>::Disconnect(BasicEvent<delegate, Args...>::Connection &conn) {
     listeners.erase(std::remove(listeners.begin(), listeners.end(), 99), listeners.end());
 }
 
-/// The default event which uses a std::function as the delegate.
+/// Event is a generic event type. It is more often we will be using a void function rather than a function-like object.
 template <typename ... Args>
 using Event = BasicEvent<std::function<void(Args...)>, Args...>;
 

main.cpp

@@ -1,156 +1,47 @@
 #include <iostream>
 #include <functional>
 #include <Event.h>
-#include <cmath>
+//#include <EventConnection.h>
+//#include "bullshit.h"
+#include "stack"
 
 void ProcessMessage(const std::string& message)
 {
-    //std::cout << "Received: " << message << std::endl;
+    std::cout << "Received: " << message << std::endl;
 }
 
-
-int SigFigsTable[] = {0,0,0,1,0,0,1,0,0,1};
-
-int DivBy[] = {1,1,1, 1000,1000,1000, 1000000, 1000000, 1000000, 1000000000, 1000000000,1000000000};
-
-std::vector<std::string> Suffixes = {
-        "", "", "",
-        " Thousand", " Thousand", " Thousand",
-        " Million", " Million", " Million",
-        " Billion", " Billion", " Billion",
-        " Trillion", " Trillion", " Trillion",
-        " Quadrillion", " Quadrillion", " Quadrillion"
-};
-
-float Round(float f, float decimalPlaces) {
-    float mult = std::pow(10, decimalPlaces);
-    return std::floor(f * mult + 0.5f) / mult;
-}
-
-float Sign(float f) { return f >= 0.f ? 1.f : -1.f;}
-
-std::string Truncate(float input) {
-
-    std::stringstream ss;
-    std::string str = "";
-
-    if (input < 1000)
-        ss << std::fixed << std::setprecision(0) << input;
-    else {
-        int figs = std::ceil(std::log10(input)) - 1;
-        auto suffix = Suffixes[figs];
-        auto roundTo = SigFigsTable[figs];
-        auto divBy = DivBy[figs];
-        auto fractional = input / (float)divBy;
-
-        // Increment roundTo for extra precision!!
-
-        ss << std::fixed << std::setprecision(roundTo) << fractional << suffix;
-    }
-
-
-
-    str = ss.str();
-    return str;
-
-}
+// TODO: BasicEvent tests here.
 
 int main() {
-
-    Event<int> very_simple_event;
-
-    very_simple_event += [] (int i) { std::cout << i+5 << std::endl; };
-    very_simple_event.Invoke(69);
-
-    //Const string reference
-    BasicEvent<std::function<void(const std::string&)>, const std::string&> OnMessage;
-    auto handler = OnMessage += [&] (const std::string& message)
-    {
-        //std::cout << "GOTS A MESSAGE: " << message << std::endl;
-    };
-
-    //void
+    BasicEvent<std::function<void(std::string)>, std::string> OnMessage;
     BasicEvent<std::function<void()>> VoidDelegate;
-    auto handler2 = OnMessage += ProcessMessage;
-
-    //Float
-    BasicEvent<std::function<void(float)>, float> floatEvent;
-    auto floatHandler = floatEvent += [&] (float){};
-
-    //long long
-    BasicEvent<std::function<void(unsigned long long)>, unsigned long long> longlongEvent;
-    auto longlongHandler = longlongEvent += [&] (unsigned long long){};
 
     bool run = true;
-    auto start = std::chrono::high_resolution_clock::now();
-    unsigned long long iterations = 0;
+
+    auto handler = OnMessage += [&] (const std::string& message)
+    {
+        std::cout << "GOTS A MESSAGE: " << message << std::endl;
+    };
+    auto handler2 = OnMessage += ProcessMessage;
+
+    auto handler3 = OnMessage += [&] {
+        std::cout << "Connect to event, with default callback, if we don't care about using the provided arguments." << std::endl;
+    };
 
     while (run)
     {
-        std::string input = "test";
+        std::string input;
+        std::cin >> input;
         OnMessage.Invoke(input);
-        OnMessage(input);
-        iterations++;
-
-        auto now = std::chrono::high_resolution_clock::now();
-        std::chrono::duration<double> elapsed = now - start;
-        if (elapsed.count() >= 1.0)
-            break;
-    }
-
-    std::cout << "std::string& iterations in 1 second: " << Truncate(iterations) << std::endl;
-    start = std::chrono::high_resolution_clock::now();
-    iterations = 0;
-
-    while (run)
-    {
         VoidDelegate.Invoke();
+        OnMessage(input);
         VoidDelegate();
-        iterations++;
-
-        auto now = std::chrono::high_resolution_clock::now();
-        std::chrono::duration<double> elapsed = now - start;
-        if (elapsed.count() >= 1.0)
-            break;
-    }
-    std::cout << "void iterations in 1 second: " << Truncate(iterations) << std::endl;
-
-    start = std::chrono::high_resolution_clock::now();
-    iterations = 0;
-
-    while (run)
-    {
-        floatEvent.Invoke(1.25);
-        floatEvent(1.25);
-        iterations++;
-
-        auto now = std::chrono::high_resolution_clock::now();
-        std::chrono::duration<double> elapsed = now - start;
-        if (elapsed.count() >= 1.0)
-            break;
     }
 
-    std::cout << "float iterations in 1 second: " << Truncate(iterations) << std::endl;
 
-    start = std::chrono::high_resolution_clock::now();
-    iterations = 0;
-
-    while (run)
-    {
-        longlongEvent.Invoke(20);
-        longlongEvent(20);
-        iterations++;
-
-        auto now = std::chrono::high_resolution_clock::now();
-        std::chrono::duration<double> elapsed = now - start;
-        if (elapsed.count() >= 1.0)
-            break;
-    }
-    std::cout << "long long iterations in 1 second: " << Truncate(iterations) << std::endl;
     return 0;
 }
 
-
 #ifdef _WIN32
 extern "C" {
     int wmain(int argc, wchar_t* argv[]) {