//  (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