Hi, Boost.MultiIndex indices, which are not copyable, interoperate with Boost.Foreach by defining the following: template<typename SuperMeta,typename TagList> inline boost::mpl::true_* boost_foreach_is_noncopyable( boost::multi_index::detail::sequenced_index<SuperMeta,TagList>*&, boost::foreach::tag) { return 0; } Unfortunately Qt (in some configuration modes, at least), defines a macro foreach to Q_FOREACH, which produces the following problem, even if Boost.Foreach was not intended to be used: http://tinyurl.com/nq52xho My question is: would it be OK if the code above was rewritten like template<typename SuperMeta,typename TagList> inline boost::mpl::true_* boost_foreach_is_noncopyable( boost::multi_index::detail::sequenced_index<SuperMeta,TagList>*&, boost_foreach_argument_dependent_lookup_hack) { return 0; } so that "foreach" is not ever mentioned? I understand that Boost.Foreach would still not work unless the macro is not defined, but this would at least save Boost.MultiIndex, which doesn't really depend on Boost.Foreach. Thanks for your comments, Joaquín M López Muñoz Telefónica