FWIW, I just started looking at Jeremy Siek's concept checking tools, and my compiler(*) came up with a warning about name hiding which is trivial to fix. I was using ContainerConcept, and it uses a method argument with the same name as a data member. The fix looks like: *** concept_check.hpp Fri Dec 27 16:51:51 2002 --- concept_check.hpp Thu Jan 2 16:13:03 2003 *************** *** 708,719 **** function_requires< AssignableConcept<Container> >(); const_constraints(c); } ! void const_constraints(const Container& c) { ! i = c.begin(); ! i = c.end(); ! n = c.size(); ! n = c.max_size(); ! b = c.empty(); } Container c; bool b; --- 708,719 ---- function_requires< AssignableConcept<Container> >(); const_constraints(c); } ! void const_constraints(const Container& cc) { ! i = cc.begin(); ! i = cc.end(); ! n = cc.size(); ! n = cc.max_size(); ! b = cc.empty(); } Container c; bool b; There are a few other classes in there which do the same thing, but this is the only one I'm currently using. --- (*) Sun Forte 6.2.1