README.md

event_channel is a C++14 exploration project. It is yet another event-dispatcher/message-bus/signal-slot framework. As such, you'll probably be better served by Boost.Signals2.

After having used a handful of messaging frameworks that forced the user to wrap messages and message handlers in boilerplate code, I set on to discover whether this was strictly necessary. That is, can I come up with a framework that given a function foo(int), can send an int to that function asynchronously without having to provide the framework a wrapped foo(int) and a wrapped int.

Here's an example of what I am trying to avoid:

void foo(int)
{}

// Must wrap event data in some "event" class which itself must derive from some base "event" class.
class my_event : public the_framework::event_base
{
    int data_;
};

// Must wrap event handler in some handler functor which itself must derive from some base "handler" class.
class my_event_foo_handler : public the_framework::event_handler_base<my_event>
{
public:
    void operator()(my_event const& e)
    {
        foo(e.data_);
    }
};

the_framework::dispatcher d;
 
my_event_foo_handler h;
d.subscribe(h);
 
my_event e{22};
d.send(e);  // foo(22) is invoked on some other thread.

Depending on the framework in question, the wrapping code will be error-prone, tediously boilerplate or both. The ideal scenario is this one:

void foo(int)
{}

the_framework::dispatcher d;

d.subscribe(foo);

d.send(22);  // foo(22) is invoked on some other thread.

Obviously, I can't restrict this framework to ints and global functions. This framework allows messages of any type and handlers of multiple nature (i.e. global functions, member functions and generic callables).

event_channel is a single header file found in include/.

Documentation and much more prose can be found here.