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