Chris@16: //-----------------------------------------------------------------------------
Chris@16: // boost variant/detail/apply_visitor_binary.hpp header file
Chris@16: // See http://www.boost.org for updates, documentation, and revision history.
Chris@16: //-----------------------------------------------------------------------------
Chris@16: //
Chris@101: // Copyright (c) 2002-2003 Eric Friedman
Chris@101: // Copyright (c) 2014 Antony Polukhin
Chris@16: //
Chris@16: // Distributed under the Boost Software License, Version 1.0. (See
Chris@16: // accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: #ifndef BOOST_VARIANT_DETAIL_APPLY_VISITOR_BINARY_HPP
Chris@16: #define BOOST_VARIANT_DETAIL_APPLY_VISITOR_BINARY_HPP
Chris@16: 
Chris@16: #include "boost/config.hpp"
Chris@16: #include "boost/detail/workaround.hpp"
Chris@16: #include "boost/variant/detail/generic_result_type.hpp"
Chris@16: 
Chris@16: #include "boost/variant/detail/apply_visitor_unary.hpp"
Chris@16: 
Chris@16: #if BOOST_WORKAROUND(__EDG__, BOOST_TESTED_AT(302))
Chris@16: #include "boost/utility/enable_if.hpp"
Chris@16: #include "boost/mpl/not.hpp"
Chris@16: #include "boost/type_traits/is_const.hpp"
Chris@16: #endif
Chris@16: 
Chris@101: 
Chris@101: #if !defined(BOOST_NO_CXX14_DECLTYPE_AUTO) && !defined(BOOST_NO_CXX11_DECLTYPE_N3276)
Chris@101: #   include "boost/variant/detail/has_result_type.hpp"
Chris@101: #endif
Chris@101: 
Chris@16: namespace boost {
Chris@16: 
Chris@16: //////////////////////////////////////////////////////////////////////////
Chris@16: // function template apply_visitor(visitor, visitable1, visitable2)
Chris@16: //
Chris@16: // Visits visitable1 and visitable2 such that their values (which we
Chris@16: // shall call x and y, respectively) are used as arguments in the
Chris@16: // expression visitor(x, y).
Chris@16: //
Chris@16: 
Chris@16: namespace detail { namespace variant {
Chris@16: 
Chris@16: template <typename Visitor, typename Value1>
Chris@16: class apply_visitor_binary_invoke
Chris@16: {
Chris@16: public: // visitor typedefs
Chris@16: 
Chris@16:     typedef typename Visitor::result_type
Chris@16:         result_type;
Chris@16: 
Chris@16: private: // representation
Chris@16: 
Chris@16:     Visitor& visitor_;
Chris@16:     Value1& value1_;
Chris@16: 
Chris@16: public: // structors
Chris@16: 
Chris@101:     apply_visitor_binary_invoke(Visitor& visitor, Value1& value1) BOOST_NOEXCEPT
Chris@16:         : visitor_(visitor)
Chris@16:         , value1_(value1)
Chris@16:     {
Chris@16:     }
Chris@16: 
Chris@16: public: // visitor interfaces
Chris@16: 
Chris@16:     template <typename Value2>
Chris@16:         BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type)
Chris@16:     operator()(Value2& value2)
Chris@16:     {
Chris@16:         return visitor_(value1_, value2);
Chris@16:     }
Chris@16: 
Chris@16: private:
Chris@16:     apply_visitor_binary_invoke& operator=(const apply_visitor_binary_invoke&);
Chris@16: };
Chris@16: 
Chris@16: template <typename Visitor, typename Visitable2>
Chris@16: class apply_visitor_binary_unwrap
Chris@16: {
Chris@16: public: // visitor typedefs
Chris@16: 
Chris@16:     typedef typename Visitor::result_type
Chris@16:         result_type;
Chris@16: 
Chris@16: private: // representation
Chris@16: 
Chris@16:     Visitor& visitor_;
Chris@16:     Visitable2& visitable2_;
Chris@16: 
Chris@16: public: // structors
Chris@16: 
Chris@101:     apply_visitor_binary_unwrap(Visitor& visitor, Visitable2& visitable2) BOOST_NOEXCEPT
Chris@16:         : visitor_(visitor)
Chris@16:         , visitable2_(visitable2)
Chris@16:     {
Chris@16:     }
Chris@16: 
Chris@16: public: // visitor interfaces
Chris@16: 
Chris@16:     template <typename Value1>
Chris@16:         BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type)
Chris@16:     operator()(Value1& value1)
Chris@16:     {
Chris@16:         apply_visitor_binary_invoke<
Chris@16:               Visitor
Chris@16:             , Value1
Chris@16:             > invoker(visitor_, value1);
Chris@16: 
Chris@16:         return boost::apply_visitor(invoker, visitable2_);
Chris@16:     }
Chris@16: 
Chris@16: private:
Chris@16:     apply_visitor_binary_unwrap& operator=(const apply_visitor_binary_unwrap&);
Chris@16: 
Chris@16: };
Chris@16: 
Chris@16: }} // namespace detail::variant
Chris@16: 
Chris@16: //
Chris@16: // nonconst-visitor version:
Chris@16: //
Chris@16: 
Chris@16: #if !BOOST_WORKAROUND(__EDG__, BOOST_TESTED_AT(302))
Chris@16: 
Chris@16: #   define BOOST_VARIANT_AUX_APPLY_VISITOR_NON_CONST_RESULT_TYPE(V) \
Chris@16:     BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(typename V::result_type) \
Chris@16:     /**/
Chris@16: 
Chris@16: #else // EDG-based compilers
Chris@16: 
Chris@16: #   define BOOST_VARIANT_AUX_APPLY_VISITOR_NON_CONST_RESULT_TYPE(V) \
Chris@16:     typename enable_if< \
Chris@16:           mpl::not_< is_const< V > > \
Chris@16:         , BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(typename V::result_type) \
Chris@16:         >::type \
Chris@16:     /**/
Chris@16: 
Chris@16: #endif // EDG-based compilers workaround
Chris@16: 
Chris@16: template <typename Visitor, typename Visitable1, typename Visitable2>
Chris@16: inline
Chris@16:     BOOST_VARIANT_AUX_APPLY_VISITOR_NON_CONST_RESULT_TYPE(Visitor)
Chris@16: apply_visitor(
Chris@16:       Visitor& visitor
Chris@16:     , Visitable1& visitable1, Visitable2& visitable2
Chris@16:     )
Chris@16: {
Chris@16:     ::boost::detail::variant::apply_visitor_binary_unwrap<
Chris@16:           Visitor, Visitable2
Chris@16:         > unwrapper(visitor, visitable2);
Chris@16: 
Chris@16:     return boost::apply_visitor(unwrapper, visitable1);
Chris@16: }
Chris@16: 
Chris@16: #undef BOOST_VARIANT_AUX_APPLY_VISITOR_NON_CONST_RESULT_TYPE
Chris@16: 
Chris@16: //
Chris@16: // const-visitor version:
Chris@16: //
Chris@16: 
Chris@16: template <typename Visitor, typename Visitable1, typename Visitable2>
Chris@16: inline
Chris@16:     BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(
Chris@16:           typename Visitor::result_type
Chris@16:         )
Chris@16: apply_visitor(
Chris@16:       const Visitor& visitor
Chris@16:     , Visitable1& visitable1, Visitable2& visitable2
Chris@16:     )
Chris@16: {
Chris@16:     ::boost::detail::variant::apply_visitor_binary_unwrap<
Chris@16:           const Visitor, Visitable2
Chris@16:         > unwrapper(visitor, visitable2);
Chris@16: 
Chris@16:     return boost::apply_visitor(unwrapper, visitable1);
Chris@16: }
Chris@16: 
Chris@101: 
Chris@101: #if !defined(BOOST_NO_CXX14_DECLTYPE_AUTO) && !defined(BOOST_NO_CXX11_DECLTYPE_N3276)
Chris@101: 
Chris@101: //////////////////////////////////////////////////////////////////////////
Chris@101: // function template apply_visitor(visitor, visitable1, visitable2)
Chris@101: //
Chris@101: // C++14 part.
Chris@101: //
Chris@101: 
Chris@101: namespace detail { namespace variant {
Chris@101: 
Chris@101: template <typename Visitor, typename Value1>
Chris@101: class apply_visitor_binary_invoke_cpp14
Chris@101: {
Chris@101:     Visitor& visitor_;
Chris@101:     Value1& value1_;
Chris@101: 
Chris@101: public: // structors
Chris@101: 
Chris@101:     apply_visitor_binary_invoke_cpp14(Visitor& visitor, Value1& value1) BOOST_NOEXCEPT
Chris@101:         : visitor_(visitor)
Chris@101:         , value1_(value1)
Chris@101:     {
Chris@101:     }
Chris@101: 
Chris@101: public: // visitor interfaces
Chris@101: 
Chris@101:     template <typename Value2>
Chris@101:     decltype(auto) operator()(Value2& value2)
Chris@101:     {
Chris@101:         return visitor_(value1_, value2);
Chris@101:     }
Chris@101: 
Chris@101: private:
Chris@101:     apply_visitor_binary_invoke_cpp14& operator=(const apply_visitor_binary_invoke_cpp14&);
Chris@101: };
Chris@101: 
Chris@101: template <typename Visitor, typename Visitable2>
Chris@101: class apply_visitor_binary_unwrap_cpp14
Chris@101: {
Chris@101:     Visitor& visitor_;
Chris@101:     Visitable2& visitable2_;
Chris@101: 
Chris@101: public: // structors
Chris@101: 
Chris@101:     apply_visitor_binary_unwrap_cpp14(Visitor& visitor, Visitable2& visitable2) BOOST_NOEXCEPT
Chris@101:         : visitor_(visitor)
Chris@101:         , visitable2_(visitable2)
Chris@101:     {
Chris@101:     }
Chris@101: 
Chris@101: public: // visitor interfaces
Chris@101: 
Chris@101:     template <typename Value1>
Chris@101:     decltype(auto) operator()(Value1& value1)
Chris@101:     {
Chris@101:         apply_visitor_binary_invoke_cpp14<
Chris@101:               Visitor
Chris@101:             , Value1
Chris@101:             > invoker(visitor_, value1);
Chris@101: 
Chris@101:         return boost::apply_visitor(invoker, visitable2_);
Chris@101:     }
Chris@101: 
Chris@101: private:
Chris@101:     apply_visitor_binary_unwrap_cpp14& operator=(const apply_visitor_binary_unwrap_cpp14&);
Chris@101: };
Chris@101: 
Chris@101: }} // namespace detail::variant
Chris@101: 
Chris@101: template <typename Visitor, typename Visitable1, typename Visitable2>
Chris@101: inline decltype(auto) apply_visitor(Visitor& visitor, Visitable1& visitable1, Visitable2& visitable2,
Chris@101:     typename boost::disable_if<
Chris@101:         boost::detail::variant::has_result_type<Visitor>
Chris@101:     >::type* = 0)
Chris@101: {
Chris@101:     ::boost::detail::variant::apply_visitor_binary_unwrap_cpp14<
Chris@101:           Visitor, Visitable2
Chris@101:         > unwrapper(visitor, visitable2);
Chris@101: 
Chris@101:     return boost::apply_visitor(unwrapper, visitable1);
Chris@101: }
Chris@101: 
Chris@101: template <typename Visitor, typename Visitable1, typename Visitable2>
Chris@101: inline decltype(auto) apply_visitor(const Visitor& visitor, Visitable1& visitable1, Visitable2& visitable2,
Chris@101:     typename boost::disable_if<
Chris@101:         boost::detail::variant::has_result_type<Visitor>
Chris@101:     >::type* = 0)
Chris@101: {
Chris@101:     ::boost::detail::variant::apply_visitor_binary_unwrap_cpp14<
Chris@101:           const Visitor, Visitable2
Chris@101:         > unwrapper(visitor, visitable2);
Chris@101: 
Chris@101:     return boost::apply_visitor(unwrapper, visitable1);
Chris@101: }
Chris@101: 
Chris@101: #endif // !defined(BOOST_NO_CXX14_DECLTYPE_AUTO) && !defined(BOOST_NO_CXX11_DECLTYPE_N3276)
Chris@16: 
Chris@16: } // namespace boost
Chris@16: 
Chris@16: #endif // BOOST_VARIANT_DETAIL_APPLY_VISITOR_BINARY_HPP