Dear all, I was playing with the serialization library, and ran into the BOOST_STRONG_TYPEDEF. In our own development environment we have a similar feature based on the article 'True typedefs' from Matthew Wilson (CUJ march 2003): BOOST_STRONG_TYPEDEF(long, HBLA); BOOST_STRONG_TYPEDEF(long, HBLUB); HBLABLA hBla(1); HBLUB hBlub(3); bool bOk = false; bOk = (hBlub == hBla); //rejected if base types are different bOk = (hBlub != hBla); //does not compile on VC 7.1 bOk = (hBlub < hBla); //rejected if base types are different hBlub = hBla; //accepted by boost_strong_typedef, this is a deliberate choice So I guess one can discuss about some behavior. But perhaps if it supports '==', it should also support '!='? Wkr, me