forked from boostorg/utility
94 lines
1.9 KiB
C++
94 lines
1.9 KiB
C++
//
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// Copyright 2003 © The Trustees of Indiana University. All rights
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// reserved.
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//
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// See the file enable_if_LICENSE for licensing conditions.
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//
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// Authors: Jaakko Järvi (jajarvi@osl.iu.edu)
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// Jeremiah Willcock (jewillco@osl.iu.edu)
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// Andrew Lumsdaine (lums@osl.iu.edu)
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//
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#include <boost/test/minimal.hpp>
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#include <boost/mpl/not.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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using boost::lazy_enable_if;
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using boost::lazy_disable_if;
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using boost::lazy_enable_if_c;
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using boost::lazy_disable_if_c;
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using boost::is_arithmetic;
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template <class T>
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struct some_traits {
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BOOST_STATIC_CONSTANT(bool, value = false);
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};
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template <>
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struct some_traits<int> {
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BOOST_STATIC_CONSTANT(bool, value = true);
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typedef bool type;
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};
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template <>
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struct some_traits<double> {
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BOOST_STATIC_CONSTANT(bool, value = true);
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typedef bool type;
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};
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template <class T>
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struct make_bool {
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typedef bool type;
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};
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template <>
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struct make_bool<int> {};
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template <>
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struct make_bool<double> {};
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namespace A {
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template<class T>
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typename lazy_enable_if<some_traits<T>, some_traits<T> >::type
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foo(T t) { return true; }
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template<class T>
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typename lazy_enable_if_c<some_traits<T>::value, some_traits<T> >::type
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foo2(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 lazy_disable_if<some_traits<T>, make_bool<T> >::type
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foo(T t) { return false; }
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template<class T>
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typename lazy_disable_if_c<some_traits<T>::value, make_bool<T> >::type
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foo2(T t) { return false; }
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}
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int test_main(int, char*[])
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{
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using namespace A;
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using namespace B;
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BOOST_TEST(foo(1));
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BOOST_TEST(foo(1.0));
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BOOST_TEST(!foo("1"));
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BOOST_TEST(!foo(static_cast<void*>(0)));
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BOOST_TEST(foo2(1));
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BOOST_TEST(foo2(1.0));
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BOOST_TEST(!foo2("1"));
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BOOST_TEST(!foo2(static_cast<void*>(0)));
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return 0;
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}
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