Boost C++ Libraries

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libs/signals2/example/hello_world_slot.cpp

// Beginner hello world example for Boost.Signals2
// Copyright Douglas Gregor 2001-2004.
// Copyright Frank Mori Hess 2009.
//
// Use, modification and
// distribution is subject to the Boost Software License, Version
// 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
// For more information, see http://www.boost.org

#include <iostream>
#include <boost/signals2/signal.hpp>

//[ hello_world_def_code_snippet
struct HelloWorld
{
  void operator()() const
  {
    std::cout << "Hello, World!" << std::endl;
  }
};
//]

int main()
{
//[ hello_world_single_code_snippet
  // Signal with no arguments and a void return value
  boost::signals2::signal<void ()> sig;

  // Connect a HelloWorld slot
  HelloWorld hello;
  sig.connect(hello);

  // Call all of the slots
  sig();
//]

  return 0;
};