// (C) Copyright Steve Cleary, Beman Dawes, Howard Hinnant & John Maddock 2000. // Use, modification and distribution are 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). // // See http://www.boost.org/libs/utility for most recent version including documentation. // call_traits: defines typedefs for function usage // (see libs/utility/call_traits.htm) /* Release notes: 23rd July 2000: Fixed array specialization. (JM) Added Borland specific fixes for reference types (issue raised by Steve Cleary). */ #ifndef BOOST_DETAIL_CALL_TRAITS_HPP #define BOOST_DETAIL_CALL_TRAITS_HPP #ifndef BOOST_CONFIG_HPP #include <boost/config.hpp> #endif #include <cstddef> #include <boost/type_traits/is_arithmetic.hpp> #include <boost/type_traits/is_pointer.hpp> #include <boost/detail/workaround.hpp> namespace boost{ namespace detail{ template <typename T, bool small_> struct ct_imp2 { typedef const T& param_type; }; template <typename T> struct ct_imp2<T, true> { typedef const T param_type; }; template <typename T, bool isp, bool b1> struct ct_imp { typedef const T& param_type; }; template <typename T, bool isp> struct ct_imp<T, isp, true> { typedef typename ct_imp2<T, sizeof(T) <= sizeof(void*)>::param_type param_type; }; template <typename T, bool b1> struct ct_imp<T, true, b1> { typedef const T param_type; }; } template <typename T> struct call_traits { public: typedef T value_type; typedef T& reference; typedef const T& const_reference; // // C++ Builder workaround: we should be able to define a compile time // constant and pass that as a single template parameter to ct_imp<T,bool>, // however compiler bugs prevent this - instead pass three bool's to // ct_imp<T,bool,bool,bool> and add an extra partial specialisation // of ct_imp to handle the logic. (JM) typedef typename boost::detail::ct_imp< T, ::boost::is_pointer<T>::value, ::boost::is_arithmetic<T>::value >::param_type param_type; }; template <typename T> struct call_traits<T&> { typedef T& value_type; typedef T& reference; typedef const T& const_reference; typedef T& param_type; // hh removed const }; #if BOOST_WORKAROUND( __BORLANDC__, < 0x5A0 ) // these are illegal specialisations; cv-qualifies applied to // references have no effect according to [8.3.2p1], // C++ Builder requires them though as it treats cv-qualified // references as distinct types... template <typename T> struct call_traits<T&const> { typedef T& value_type; typedef T& reference; typedef const T& const_reference; typedef T& param_type; // hh removed const }; template <typename T> struct call_traits<T&volatile> { typedef T& value_type; typedef T& reference; typedef const T& const_reference; typedef T& param_type; // hh removed const }; template <typename T> struct call_traits<T&const volatile> { typedef T& value_type; typedef T& reference; typedef const T& const_reference; typedef T& param_type; // hh removed const }; template <typename T> struct call_traits< T * > { typedef T * value_type; typedef T * & reference; typedef T * const & const_reference; typedef T * const param_type; // hh removed const }; #endif #if !defined(BOOST_NO_ARRAY_TYPE_SPECIALIZATIONS) template <typename T, std::size_t N> struct call_traits<T [N]> { private: typedef T array_type[N]; public: // degrades array to pointer: typedef const T* value_type; typedef array_type& reference; typedef const array_type& const_reference; typedef const T* const param_type; }; template <typename T, std::size_t N> struct call_traits<const T [N]> { private: typedef const T array_type[N]; public: // degrades array to pointer: typedef const T* value_type; typedef array_type& reference; typedef const array_type& const_reference; typedef const T* const param_type; }; #endif } #endif // BOOST_DETAIL_CALL_TRAITS_HPP