Chris@16: //  (C) Copyright Steve Cleary, Beman Dawes, Howard Hinnant & John Maddock 2000.
Chris@16: //  Use, modification and distribution are subject to the Boost Software License,
Chris@16: //  Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: //  http://www.boost.org/LICENSE_1_0.txt).
Chris@16: //
Chris@16: //  See http://www.boost.org/libs/utility for most recent version including documentation.
Chris@16: 
Chris@16: // call_traits: defines typedefs for function usage
Chris@16: // (see libs/utility/call_traits.htm)
Chris@16: 
Chris@16: /* Release notes:
Chris@16:    23rd July 2000:
Chris@16:       Fixed array specialization. (JM)
Chris@16:       Added Borland specific fixes for reference types
Chris@16:       (issue raised by Steve Cleary).
Chris@16: */
Chris@16: 
Chris@16: #ifndef BOOST_DETAIL_CALL_TRAITS_HPP
Chris@16: #define BOOST_DETAIL_CALL_TRAITS_HPP
Chris@16: 
Chris@16: #ifndef BOOST_CONFIG_HPP
Chris@16: #include <boost/config.hpp>
Chris@16: #endif
Chris@16: #include <cstddef>
Chris@16: 
Chris@16: #include <boost/type_traits/is_arithmetic.hpp>
Chris@16: #include <boost/type_traits/is_enum.hpp>
Chris@16: #include <boost/type_traits/is_pointer.hpp>
Chris@16: #include <boost/detail/workaround.hpp>
Chris@16: 
Chris@16: namespace boost{
Chris@16: 
Chris@16: namespace detail{
Chris@16: 
Chris@16: template <typename T, bool small_>
Chris@16: struct ct_imp2
Chris@16: {
Chris@16:    typedef const T& param_type;
Chris@16: };
Chris@16: 
Chris@16: template <typename T>
Chris@16: struct ct_imp2<T, true>
Chris@16: {
Chris@16:    typedef const T param_type;
Chris@16: };
Chris@16: 
Chris@16: template <typename T, bool isp, bool b1, bool b2>
Chris@16: struct ct_imp
Chris@16: {
Chris@16:    typedef const T& param_type;
Chris@16: };
Chris@16: 
Chris@16: template <typename T, bool isp, bool b2>
Chris@16: struct ct_imp<T, isp, true, b2>
Chris@16: {
Chris@16:    typedef typename ct_imp2<T, sizeof(T) <= sizeof(void*)>::param_type param_type;
Chris@16: };
Chris@16: 
Chris@16: template <typename T, bool isp, bool b1>
Chris@16: struct ct_imp<T, isp, b1, true>
Chris@16: {
Chris@16:    typedef typename ct_imp2<T, sizeof(T) <= sizeof(void*)>::param_type param_type;
Chris@16: };
Chris@16: 
Chris@16: template <typename T, bool b1, bool b2>
Chris@16: struct ct_imp<T, true, b1, b2>
Chris@16: {
Chris@16:    typedef const T param_type;
Chris@16: };
Chris@16: 
Chris@16: }
Chris@16: 
Chris@16: template <typename T>
Chris@16: struct call_traits
Chris@16: {
Chris@16: public:
Chris@16:    typedef T value_type;
Chris@16:    typedef T& reference;
Chris@16:    typedef const T& const_reference;
Chris@16:    //
Chris@16:    // C++ Builder workaround: we should be able to define a compile time
Chris@16:    // constant and pass that as a single template parameter to ct_imp<T,bool>,
Chris@16:    // however compiler bugs prevent this - instead pass three bool's to
Chris@16:    // ct_imp<T,bool,bool,bool> and add an extra partial specialisation
Chris@16:    // of ct_imp to handle the logic. (JM)
Chris@16:    typedef typename boost::detail::ct_imp<
Chris@16:       T,
Chris@16:       ::boost::is_pointer<T>::value,
Chris@16:       ::boost::is_arithmetic<T>::value,
Chris@16:       ::boost::is_enum<T>::value
Chris@16:    >::param_type param_type;
Chris@16: };
Chris@16: 
Chris@16: template <typename T>
Chris@16: struct call_traits<T&>
Chris@16: {
Chris@16:    typedef T& value_type;
Chris@16:    typedef T& reference;
Chris@16:    typedef const T& const_reference;
Chris@16:    typedef T& param_type;  // hh removed const
Chris@16: };
Chris@16: 
Chris@16: #if BOOST_WORKAROUND( __BORLANDC__,  < 0x5A0 )
Chris@16: // these are illegal specialisations; cv-qualifies applied to
Chris@16: // references have no effect according to [8.3.2p1],
Chris@16: // C++ Builder requires them though as it treats cv-qualified
Chris@16: // references as distinct types...
Chris@16: template <typename T>
Chris@16: struct call_traits<T&const>
Chris@16: {
Chris@16:    typedef T& value_type;
Chris@16:    typedef T& reference;
Chris@16:    typedef const T& const_reference;
Chris@16:    typedef T& param_type;  // hh removed const
Chris@16: };
Chris@16: template <typename T>
Chris@16: struct call_traits<T&volatile>
Chris@16: {
Chris@16:    typedef T& value_type;
Chris@16:    typedef T& reference;
Chris@16:    typedef const T& const_reference;
Chris@16:    typedef T& param_type;  // hh removed const
Chris@16: };
Chris@16: template <typename T>
Chris@16: struct call_traits<T&const volatile>
Chris@16: {
Chris@16:    typedef T& value_type;
Chris@16:    typedef T& reference;
Chris@16:    typedef const T& const_reference;
Chris@16:    typedef T& param_type;  // hh removed const
Chris@16: };
Chris@16: 
Chris@16: template <typename T>
Chris@16: struct call_traits< T * >
Chris@16: {
Chris@16:    typedef T * value_type;
Chris@16:    typedef T * & reference;
Chris@16:    typedef T * const & const_reference;
Chris@16:    typedef T * const param_type;  // hh removed const
Chris@16: };
Chris@16: #endif
Chris@16: #if !defined(BOOST_NO_ARRAY_TYPE_SPECIALIZATIONS)
Chris@16: template <typename T, std::size_t N>
Chris@16: struct call_traits<T [N]>
Chris@16: {
Chris@16: private:
Chris@16:    typedef T array_type[N];
Chris@16: public:
Chris@16:    // degrades array to pointer:
Chris@16:    typedef const T* value_type;
Chris@16:    typedef array_type& reference;
Chris@16:    typedef const array_type& const_reference;
Chris@16:    typedef const T* const param_type;
Chris@16: };
Chris@16: 
Chris@16: template <typename T, std::size_t N>
Chris@16: struct call_traits<const T [N]>
Chris@16: {
Chris@16: private:
Chris@16:    typedef const T array_type[N];
Chris@16: public:
Chris@16:    // degrades array to pointer:
Chris@16:    typedef const T* value_type;
Chris@16:    typedef array_type& reference;
Chris@16:    typedef const array_type& const_reference;
Chris@16:    typedef const T* const param_type;
Chris@16: };
Chris@16: #endif
Chris@16: 
Chris@16: }
Chris@16: 
Chris@16: #endif // BOOST_DETAIL_CALL_TRAITS_HPP