38 lines
1.0 KiB
C++
38 lines
1.0 KiB
C++
// (C) Copyright Mathias Gaunard 2009.
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// Use, modification and distribution are subject to the
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// Boost Software License, Version 1.0. (See accompanying file
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// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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// See http://www.boost.org/libs/config for the most recent version.
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// MACRO: BOOST_NO_SFINAE_EXPR
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// TITLE: SFINAE for expressions
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// DESCRIPTION: SFINAE for expressions not supported.
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namespace boost_no_sfinae_expr
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{
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template<typename T>
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struct has_foo
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{
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typedef char NotFound;
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struct Found { char x[2]; };
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template<int> struct dummy {};
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template<class X> static Found test(dummy< sizeof((*(X*)0).foo(), 0) >*);
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template<class X> static NotFound test( ... );
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static const bool value = (sizeof(Found) == sizeof(test<T>(0)));
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};
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struct test1 {};
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struct test2 { void foo(); };
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int test()
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{
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return has_foo<test1>::value || !has_foo<test2>::value;
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}
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} // namespace boost_no_sfinae_expr
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