oh, sorry for the forgotten < My code was not very aesy to read... Anyway, you're response is very helpful for me :-D !! I think that std::pair will works... Thanks you very much, Tomasz!! LX

Yes, it's right !!:-O What I want to do is based on STL : ------------------------------------------ typedef struct _MYSTRUCTURE { long lType; long lSubType; }MYSTRUCTURE; typedef std::vector lID; typedef std::map myMap; ------------------------------------------- But when I do a 'find.' on myMap, STL can't find my vector in searching on MYSTRUCTURE 'cause it can't compare : ... ---- MYSTRUCTURE myStructure; myStructure.lType = 10; myStructure.lSubType = 11; myMap::iterator it; it = m_mymap.find(myStructure); ---- So, I wanted to concatenated the 2 longs and using typedef std::map myMap; but, you're right : double and long are two differents animals... Do you see a solution ? LX

Do you know if it is possible to create an 64-bit value (double) by concatenating two specified 32-bit values (long)?? The macro MAKELONG exists but MAKEDOUBLE, no...Apparently, it is not possible to make a << on a double?? Do you know a way to do it? Thanks, LX