forked from boostorg/core
51 lines
1.2 KiB
C++
51 lines
1.2 KiB
C++
// Boost enable_if library
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// Copyright 2003 (c) The Trustees of Indiana University.
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// Use, modification, and distribution is subject to the Boost Software
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// License, Version 1.0. (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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// Authors: Jaakko Jarvi (jajarvi at osl.iu.edu)
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// Jeremiah Willcock (jewillco at osl.iu.edu)
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// Andrew Lumsdaine (lums at osl.iu.edu)
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#include <boost/config.hpp>
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#include <boost/utility/enable_if.hpp>
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#include <boost/type_traits/is_arithmetic.hpp>
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#include <boost/core/lightweight_test.hpp>
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using boost::enable_if;
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using boost::is_arithmetic;
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template<class T> struct not_
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{
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BOOST_STATIC_CONSTANT( bool, value = !T::value );
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};
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namespace A {
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template<class T>
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typename enable_if<is_arithmetic<T>, bool>::type
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arithmetic_object(T t) { return true; }
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}
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namespace B {
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template<class T>
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typename enable_if<not_<is_arithmetic<T> >, bool>::type
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arithmetic_object(T t) { return false; }
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}
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int main()
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{
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using namespace A;
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using namespace B;
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BOOST_TEST(arithmetic_object(1));
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BOOST_TEST(arithmetic_object(1.0));
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BOOST_TEST(!arithmetic_object("1"));
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BOOST_TEST(!arithmetic_object(static_cast<void*>(0)));
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return boost::report_errors();
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}
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