47 lines
865 B
C++
47 lines
865 B
C++
/*
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Copyright 2017 Glen Joseph Fernandes
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(glenjofe@gmail.com)
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Distributed under Boost Software License, Version 1.0.
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(See accompanying file LICENSE_1_0.txt or copy at
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http://www.boost.org/LICENSE_1_0.txt)
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*/
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// MACRO: BOOST_NO_CXX11_SFINAE_EXPR
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// TITLE: C++11 SFINAE for expressions
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// DESCRIPTION: C++11 SFINAE for expressions not supported.
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namespace boost_no_cxx11_sfinae_expr {
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template<class>
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struct ignore {
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typedef void type;
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};
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template<class T>
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T& object();
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template<class T, class E = void>
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struct trait {
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static const int value = 0;
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};
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template<class T>
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struct trait<T, typename ignore<decltype(&object<T>())>::type> { };
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template<class T>
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struct result {
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static const int value = T::value;
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};
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class type {
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void operator&() const { }
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};
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int test()
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{
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return result<trait<type> >::value;
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}
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} /* boost_no_cxx11_sfinae_expr */
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