| // Boost.Signals library |
| |
| // Copyright Douglas Gregor 2001-2004. |
| // Copyright Frank Mori Hess 2007. 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 |
| |
| #ifndef BOOST_SIGNALS2_SIGNALS_COMMON_HPP |
| #define BOOST_SIGNALS2_SIGNALS_COMMON_HPP |
| |
| #include <boost/mpl/bool.hpp> |
| #include <boost/mpl/if.hpp> |
| #include <boost/ref.hpp> |
| #include <boost/signals2/signal_base.hpp> |
| #include <boost/type_traits/is_base_of.hpp> |
| |
| namespace boost { |
| namespace signals2 { |
| namespace detail { |
| // Determine if the given type T is a signal |
| template<typename T> |
| class is_signal: public mpl::bool_<is_base_of<signal_base, T>::value> |
| {}; |
| |
| // A slot can be a signal, a reference to a function object, or a |
| // function object. |
| struct signal_tag {}; |
| struct reference_tag {}; |
| struct value_tag {}; |
| |
| // Classify the given slot as a signal, a reference-to-slot, or a |
| // standard slot |
| template<typename S> |
| class get_slot_tag { |
| typedef typename mpl::if_<is_signal<S>, |
| signal_tag, value_tag>::type signal_or_value; |
| public: |
| typedef typename mpl::if_<is_reference_wrapper<S>, |
| reference_tag, |
| signal_or_value>::type type; |
| }; |
| |
| // Get the slot so that it can be copied |
| template<typename F> |
| typename F::weak_signal_type |
| get_invocable_slot(const F &signal, signal_tag) |
| { return typename F::weak_signal_type(signal); } |
| |
| template<typename F> |
| const F& |
| get_invocable_slot(const F& f, reference_tag) |
| { return f; } |
| |
| template<typename F> |
| const F& |
| get_invocable_slot(const F& f, value_tag) |
| { return f; } |
| |
| // Determines the type of the slot - is it a signal, a reference to a |
| // slot or just a normal slot. |
| template<typename F> |
| typename get_slot_tag<F>::type |
| tag_type(const F&) |
| { |
| typedef typename get_slot_tag<F>::type |
| the_tag_type; |
| the_tag_type tag = the_tag_type(); |
| return tag; |
| } |
| } // end namespace detail |
| } // end namespace signals2 |
| } // end namespace boost |
| |
| #endif // BOOST_SIGNALS2_SIGNALS_COMMON_HPP |