[boost] [fusion] How does is_pointer< Sequence > work?

Hi Joel & Dan Going through the fusion quick start, I'm wondering how the expression ... for_each(filter_if<boost::is_pointer<Sequence> >(seq), print_xml()); ... could ever work? Shouldn't that rather read similar to ... for_each(filter_if<boost::is_pointer<_> >(seq), print_xml()); ... so that the _ placeholder can be replaced with the individual types in the sequence? Thanks, -- Andreas Huber When replying by private email, please remove the words spam and trap from the address shown in the header.