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///////////////////////////////////////////////////////////////////////////////
// bug2407.hpp
//
// Copyright 2008 Eric Niebler. Distributed under 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 <iostream>
#include <boost/proto/proto.hpp>
namespace mpl = boost::mpl;
namespace proto = boost::proto;
using proto::_;
template<class E>
struct e;
struct g
: proto::or_<
proto::terminal<int>
, proto::plus<g,g>
>
{};
struct d
: proto::domain<proto::generator<e>, g>
{};
template<class E>
struct e
: proto::extends<E, e<E>, d>
{
BOOST_MPL_ASSERT((proto::matches<E, g>));
e(E const &x = E())
: proto::extends<E, e<E>, d>(x)
{}
};
e<proto::terminal<int>::type> i;
template<class E>
std::ostream &operator<<(std::ostream &sout, e<E> const &x)
{
return sout;
}
int main()
{
std::cout << (i+i);
}
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