> It's a pitfall that is easy to fall into even if you've read about > it. The correct way to implement what you want would be > > typedef typename boost::mpl::apply_if_c<(numParams > 2), > boost::mpl::at_c<TypeVector, 2>, > boost::mpl::identity<boost::mpl::void_> > >::type Param1; > > We have a whole section in the docs devoted to this issue - > http://www.boost.org/libs/mpl/doc/index.html#applyif
I've read it, but it was late and I missed the point obviously, so I am paying the price for not paying attention :) Btw, VC7.1 does not seem to like identity in this (and David's) scenario - it complains that it does not have inner typedef to type, even though it does. On the other hand, removing identity and using just void_ works as well, because void_ typedefs itself as inner 'type'. Thanks again, Drazen _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost
