Re: [Boost-users] Non-boost c++ novice help

You can only have static members defined in the class declaration, e.g. class register { void set_mask() { reg |= mask; } private: uint64_t reg; const static uint64_t mask = 0x12345678; }; This, of course, only makes sense when the mask doesn't change from every instantiation of register (being non-static). Christian