SignalsLibrary (a.k.a. slib) is simple "include and use" library that provides anonimous function pointer (slib::delegate), function arguments list (slib::args_list) and simple messaging system (slib::signal and slib::slot).

• slib::delegate is a template anonimous pointer to class method or static function. Delegates can be copied and stored in generic containers (for example, std::vector). Delegates are fast, small (it consists only of two pointers) and does not use dynamic memory allocation. #include "slib/delegate.hpp" and you are ready to use delegates. slib::delegate is redesigned idea of Sergey Ryazanov's fast delegates.
• slib::args_list is a function arguments list. It can be used to store arguments to call a lot of functions later. Any argument in list can be changed at any time. It stores arguments in std::tuple and has methods for unpacking arguments from tuple to call function/method/delegate/functor with these arguments. #include "slib/args_list.hpp" to use slib::args_list.
• slib::signal and slib::slot is simple messaging system. When signal emits, all connected slots are invoked. If you have ever used Qt and it's signal-slot system then you understand what is it. You don't need to inherit from special base-class to use signals and slots (for example, in Qt you have to inherit from QObject class to be able to use signals and slots). Multiple slots can be connected to one signal; one slot can be also connected to multiple signals; one signal can be connected to multiple signals like a slot (when parent signal emits, all connected signals emits too). Signal and slot automatically disconnects on destructor from all connected signals and slots, that's why signal and slot can not be copied or copy-constructed - they fully belong to theirs owner-object.

SignalsLibrary is using features of C 11 standard, so you have to use C 11 compatible compiler.

1. Copy all files from include/slib to to your include directory (for example, include/third_party/slib or just include/slib). Please, note that slib is using shared_allocator as a third-party library (see NOTE below).
2. Include necessary headers (slib/delegate.hpp and/or slib/args_list.hpp and/or slib/signals.hpp) and you are ready for using delegates, args_lists, signals and slots.

NOTE: slib::signal and slib::slot requires dynamic linkage with shared_allocator (instructions can be found here). slib::delegate and slib::args_list does not need shared_allocator.

#include "slib/delegate.hpp"

class A
{
public:
  int f(int x) const
  {
    return x * x;
  }
};

int g(int y)
{
  return y * 2;
}

int main()
{
  slib::delegate<int(int)> d;
  A a;
  
  // invoke unbinded delegate
  auto result0 = d(10); // result0 == 0
  
  // binding delegate to class const-method
  d.bind_const<A, &A::f>(&a); // or --- d.BIND_CONST(A, &a, f);
  
  auto result1 = d(10); // result1 == 100
  auto result2 = d(5); // result2 == 25
  
  // bindning delegate to static function
  d.bind<g>();
  
  auto result3 = d(10); // result3 == 20
  auto result4 = d(5); // result4 == 10
  
  // unbinding delegate
  d.unbind();
  
  // invoke unbinded delegate again
  auto result5 = d(5); // result5 == 0
  
  return 0;
}

SignalsLibrary is licensed under terms of GNU GPL v3 (see file LICENSE), but I plan to add more permissive licenses in the near future (LGPL or MIT licenses maybe). Send me a message if you are interested.