| // (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_enum.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, bool b2> |
| struct ct_imp |
| { |
| typedef const T& param_type; |
| }; |
| |
| template <typename T, bool isp, bool b2> |
| struct ct_imp<T, isp, true, b2> |
| { |
| typedef typename ct_imp2<T, sizeof(T) <= sizeof(void*)>::param_type param_type; |
| }; |
| |
| template <typename T, bool isp, bool b1> |
| struct ct_imp<T, isp, b1, true> |
| { |
| typedef typename ct_imp2<T, sizeof(T) <= sizeof(void*)>::param_type param_type; |
| }; |
| |
| template <typename T, bool b1, bool b2> |
| struct ct_imp<T, true, b1, b2> |
| { |
| 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, |
| ::boost::is_enum<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 |