libcruft-util/signal.hpp

/*
 * This file is part of libgim.
 *
 * libgim is free software: you can redistribute it and/or modify it under the
 * terms of the GNU General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later
 * version.
 *
 * libgim is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with libgim.  If not, see <http://www.gnu.org/licenses/>.
 *
 * Copyright 2011 Danny Robson <danny@blubinc.net>
 */

#ifndef __SIGNAL_HPP
#define __SIGNAL_HPP

#include <algorithm>
#include <vector>
#include <functional>

namespace util {
    template <typename Ret, typename ...Args>
    class signal {
        public:
            typedef Ret (*callback_function)(Args...);
            typedef std::function<Ret(Args...)> callback_object;

        protected:
            std::vector<callback_object> m_children;

        public:
            signal ()
                { m_children.reserve (16); }

            /// Add a callback to list.
            void connect (callback_object   _cb)
                { m_children.push_back (_cb); }

            /// Add a callback to the list.
            void connect (callback_function _cb)
                { m_children.push_back (_cb); }

            /// Remove all instances of callback `cb'
            //void disconnect (callback_function _cb)
            //    { disconnect (callback_object (_cb)); }

            /// Remove all instances of callback `cb'
            /*void disconnect (callback_object _cb) {
                m_children.erase (std::remove (m_children.begin (),
                                               m_children.end   (),
                                               _cb),
                                  m_children.end ());
            }*/

            /// Disconnect all callbacks
            void clear (void)
                { m_children.clear (); }

            /// Returns the number of callbacks connected.
            unsigned int size (void) const
                { return m_children.size (); }

            /// Execute all callbacks, ignoring the return parameters. Does not combine results.
            void operator () (Args... tail) {
                for (auto i = m_children.begin (), end = m_children.end (); i != end; ++i)
                    (*i)(tail...);
            }
    };
}

#endif // __SIGNAL_HPP