Hi, I've discovered several problems with BCCL while using it recently: 1. The Generator concept class uses a reference to the result type, which causes an error if the result type is a reference itself: c:\program files\boost\boost\concept_check.hpp(353) : error C2529: 'r' : reference to reference is illegal 2. The copy_constructible_archetype has a public default constructor defined - is it intentional? AFAIK it should not be there... 3. Borland 5.6.4 has problems with some concepts when using references: Error E2232 C:\Program Files\boost\boost/concept_check.hpp 426: Reference member 'BinaryPredicate<_STL::less<int>,int,const int &>::b' in class without constructors in function main() Best regards, Robert -=##############=- "I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones." - Albert Einstein