//  (C) Copyright Dave Abrahams, Steve Cleary, Beman Dawes, 

//      Howard Hinnant and John Maddock 2000. 

//  (C) Copyright Mat Marcus, Jesse Jones and Adobe Systems Inc 2001

//  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/type_traits for most recent version including documentation.

//    Fixed is_pointer, is_reference, is_const, is_volatile, is_same, 

//    is_member_pointer based on the Simulated Partial Specialization work 

//    of Mat Marcus and Jesse Jones. See  http://opensource.adobe.com or 

//    http://groups.yahoo.com/group/boost/message/5441 

//    Some workarounds in here use ideas suggested from "Generic<Programming>: 

//    Mappings between Types and Values" 

//    by Andrei Alexandrescu (see http://www.cuj.com/experts/1810/alexandr.html).

#ifndef BOOST_TT_IS_CONST_HPP_INCLUDED

#define BOOST_TT_IS_CONST_HPP_INCLUDED

#include <boost/config.hpp>

#include <boost/detail/workaround.hpp>

#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION

#   include <boost/type_traits/detail/cv_traits_impl.hpp>

#   ifdef __GNUC__

#       include <boost/type_traits/is_reference.hpp>

#   endif

#   if BOOST_WORKAROUND(BOOST_MSVC, < 1400)

#       include <boost/type_traits/remove_bounds.hpp>

#   endif

#else

#   include <boost/type_traits/is_reference.hpp>

#   include <boost/type_traits/is_array.hpp>

#   include <boost/type_traits/detail/yes_no_type.hpp>

#   include <boost/type_traits/detail/false_result.hpp>

#endif

// should be the last #include

#include <boost/type_traits/detail/bool_trait_def.hpp>

namespace boost {

#if defined( __CODEGEARC__ )

BOOST_TT_AUX_BOOL_TRAIT_DEF1(is_const,T,__is_const(T))

#elif !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)

//* is a type T  declared const - is_const<T>

#if BOOST_WORKAROUND(BOOST_MSVC, < 1400)

   BOOST_TT_AUX_BOOL_TRAIT_DEF1(is_const,T,::boost::detail::cv_traits_imp<typename remove_bounds<T>::type*>::is_const)

#else

   BOOST_TT_AUX_BOOL_TRAIT_DEF1(is_const,T,::boost::detail::cv_traits_imp<T*>::is_const)

#endif

BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_const,T&,false)

#if  defined(BOOST_ILLEGAL_CV_REFERENCES)

// 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...

BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_const,T& const,false)

BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_const,T& volatile,false)

BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_const,T& const volatile,false)

#endif

#if defined(__GNUC__) && (__GNUC__ < 3)

// special case for gcc where illegally cv-qualified reference types can be

// generated in some corner cases:

BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_const,T const,!(::boost::is_reference<T>::value))

BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC1_1(typename T,is_const,T volatile const,!(::boost::is_reference<T>::value))

#endif

#else

namespace detail {

using ::boost::type_traits::yes_type;

using ::boost::type_traits::no_type;

yes_type is_const_tester(const volatile void*);

no_type is_const_tester(volatile void *);

template <bool is_ref, bool array>

struct is_const_helper

    : ::boost::type_traits::false_result

{

};

template <>

struct is_const_helper<false,false>

{

    template <typename T> struct result_

    {

        static T* t;

        BOOST_STATIC_CONSTANT(bool, value = (

            sizeof(detail::yes_type) == sizeof(detail::is_const_tester(t))

            ));

    };

};

template <>

struct is_const_helper<false,true>

{

    template <typename T> struct result_

    {

        static T t;

        BOOST_STATIC_CONSTANT(bool, value = (

            sizeof(detail::yes_type) == sizeof(detail::is_const_tester(&t))

            ));

    };

};

template <typename T>

struct is_const_impl

    : is_const_helper<

          is_reference<T>::value

        , is_array<T>::value

        >::template result_<T>

{

};

BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_const,void,false)

#ifndef BOOST_NO_CV_VOID_SPECIALIZATIONS

BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_const,void const,true)

BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_const,void volatile,false)

BOOST_TT_AUX_BOOL_TRAIT_IMPL_SPEC1(is_const,void const volatile,true)

#endif

} // namespace detail

//* is a type T  declared const - is_const<T>

BOOST_TT_AUX_BOOL_TRAIT_DEF1(is_const,T,::boost::detail::is_const_impl<T>::value)

#endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION

} // namespace boost

#include <boost/type_traits/detail/bool_trait_undef.hpp>

#endif // BOOST_TT_IS_CONST_HPP_INCLUDED