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// (C) Copyright Steve Cleary, Beman Dawes, Aleksey Gurtovoy,
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// Howard Hinnant & John Maddock 2000.
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// Permission to copy, use, modify, sell and distribute this software is
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// granted provided this copyright notice appears in all copies. This
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// software is provided "as is" without express or implied warranty, and
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// with no claim as to its suitability for any purpose.
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// See http://www.boost.org for most recent version including documentation.
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#ifndef BOOST_TT_IS_SAME_HPP_INCLUDED
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#define BOOST_TT_IS_SAME_HPP_INCLUDED
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#include "boost/type_traits/config.hpp"
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#ifdef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
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#include "boost/type_traits/detail/yes_no_type.hpp"
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#include "boost/type_traits/detail/ice_and.hpp"
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#include "boost/type_traits/is_reference.hpp"
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// should be the last #include
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#include "boost/type_traits/detail/bool_trait_def.hpp"
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#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
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BOOST_TT_AUX_BOOL_TRAIT_DEF2(is_same,T,U,false)
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BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC2_1(typename T,is_same,T,T,true)
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// without this, Borland's compiler gives the wrong answer for
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// references to arrays:
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BOOST_TT_AUX_BOOL_TRAIT_PARTIAL_SPEC2_1(typename T,is_same,T&,T&,true)
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#else // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
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// the following VC6 specific implementation is *NOT* legal
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// C++, but has the advantage that it works for incomplete
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template< typename T1 >
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template<typename T2> struct part_2 { enum { value = false }; };
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template<> struct part_2<T1> { enum { value = true }; };
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template< typename T1, typename T2 >
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enum { value = detail::is_same_part_1<T1>::template part_2<T2>::value };
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#else // generic "no-partial-specialization" version
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::boost::type_traits::yes_type
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BOOST_TT_DECL is_same_tester(T*, T*);
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::boost::type_traits::no_type
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BOOST_TT_DECL is_same_tester(...);
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template <typename T, typename U>
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BOOST_STATIC_CONSTANT(bool, value =
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(::boost::type_traits::ice_and<
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(sizeof(type_traits::yes_type) == sizeof(detail::is_same_tester(&t,&u))),
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(::boost::is_reference<T>::value == ::boost::is_reference<U>::value),
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(sizeof(T) == sizeof(U))
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BOOST_TT_AUX_BOOL_TRAIT_DEF2(is_same,T,U,(::boost::detail::is_same_impl<T,U>::value))
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#endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
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#include "boost/type_traits/detail/bool_trait_undef.hpp"
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#endif // BOOST_TT_IS_SAME_HPP_INCLUDED