struct a {}; struct b {}; struct c {};

typedef set input; typedef set remove_these;

struct set_inserter { typedef set<> state; typedef boost::mpl::insert operation; };

typedef boost::mpl::remove_if, set_inserter>::type result;

BOOST_MPL_ASSERT((boost::mpl::equal));

Thanks alot! Works quite nicely. One thing I noticed: if input and remove_these do not share at least one common element compilation will fail (with vc8). E.g.: typedef set input; typedef set<c> remove_these; BOOST_MPL_ASSERT((boost::mpl::equal >)); It is not just that the assertion fails but the whole thing blows up (multiple pages of cryptic error messages). Is that expected? I can easily work around it by adding a dummy entry to both input and remove_these. Cheers, Alfred