// // Test that ref(ref(x)) does NOT collapse to ref(x) // // This irregularity of std::ref is questionable and breaks // existing Boost code such as proto::make_expr // // Copyright 2014 Peter Dimov // // 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 #include template void test( T const & t ) { { boost::reference_wrapper< T const > r = boost::ref( t ); BOOST_TEST_EQ( &r.get(), &t ); } { boost::reference_wrapper< T const > r = boost::cref( t ); BOOST_TEST_EQ( &r.get(), &t ); } } template void test_nonconst( T & t ) { { boost::reference_wrapper< T > r = boost::ref( t ); BOOST_TEST_EQ( &r.get(), &t ); } { boost::reference_wrapper< T const > r = boost::cref( t ); BOOST_TEST_EQ( &r.get(), &t ); } } int main() { int x = 0; test( x ); test( boost::ref( x ) ); test( boost::cref( x ) ); test_nonconst( x ); { boost::reference_wrapper< int > r = boost::ref( x ); test_nonconst( r ); } { boost::reference_wrapper< int const > r = boost::cref( x ); test_nonconst( r ); } return boost::report_errors(); }