Dear All, I think I have found a safe way to bind a temporary to a const reference and cast away the constness. This means that a temporary can be passed (relatively) safely to an algorithm with a prototype like void foo( T& t ) { // do something with t, but don't store the reference. } for example, we might want to call foo() like vector<int> make_vec(); foo( make_vec() ); but we cannot. Using a little macro, we can say foo( BOOST_LVALUE( make_vec() ) ); assuming these prototypes const vector<int> make_cvec(); const vector<int>& make_crvec(); these uses will fail at ct foo( BOOST_LVALUE( make_cvec() ) ); foo( BOOST_LVALUE( make_crvec() ) ); Comments are welcome. br Thorsten begin 666 lvalue_cast.cpp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`` ` end