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// Copyright Daniel Wallin 2006. Use, modification and distribution is
// 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)
#include <boost/parameter/preprocessor.hpp>
#include <boost/parameter/name.hpp>
#include <boost/type_traits/is_convertible.hpp>
#include <boost/tuple/tuple.hpp>
#include <string>
#include "basics.hpp"
#include <boost/utility/enable_if.hpp>
namespace test {
namespace mpl = boost::mpl;
using mpl::_;
using boost::is_convertible;
BOOST_PARAMETER_NAME(x)
// Sun has problems with this syntax:
//
// template1< r* ( template2<x> ) >
//
// Workaround: factor template2<x> into a separate typedef
#if BOOST_WORKAROUND(__SUNPRO_CC, BOOST_TESTED_AT(0x580))
typedef is_convertible<_,char const*> predicate;
BOOST_PARAMETER_FUNCTION((int), sfinae, tag,
(deduced
(optional (x, *(predicate), 0))
)
)
{
return 1;
}
#else
BOOST_PARAMETER_FUNCTION((int), sfinae, tag,
(deduced
(optional (x, *(is_convertible<_,char const*>), 0))
)
)
{
return 1;
}
#endif
template<class A0>
typename boost::enable_if<boost::is_same<int,A0>, int>::type
sfinae(A0 const& a0)
{
return 0;
}
} // namespace test
int main()
{
using namespace test;
assert(sfinae() == 1);
assert(sfinae("foo") == 1);
assert(sfinae(1) == 0);
return 0;
}
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