Hi all, I'm observing an interesting problem on MSVC71 regarding the use of __LINE__ with Boost.Preprocessor. The code looks like this ==== snip ==== #include <boost/preprocessor/cat.hpp> #define UNIQUE_ID BOOST_PP_CAT(id, __LINE__) #define UNIQUE_ID2 BOOST_PP_CAT(id, _MSC_VER) int main() { int UNIQUE_ID2 = 321; int UNIQUE_ID = 123; bool UNIQUE_ID = false; } ==== snip ==== The compiler works fine with UNIQUE_ID2, but not UNIQUE_ID. The only different in them is only the use of __LINE__ instead of _MSC_VER. Does anyone on the list has more insight on this issue? Or, what're the common ways to generate an unique identifier automatically within certain scope? Cheers, Freddie -- Wu Yinghui, Freddie Research & Development Software Engineer Volume Interactions Pte Ltd 1 Kim Seng Promenade, #12-01 Great World City East Tower Singapore 237994 Tel: +65 62226962 (Ext 216) Fax: +65 62226215 Email: yhwu@volumeinteractions.com URL: http://www.volumeinteractions.com Important: This message is intended for the recipient(s) addressed above. It contains privileged and confidential information. If you are not the intended recipient, please notify the sender immediately by replying to this message and then delete it from your system. You must not read, copy, use, or disseminate this communication in any form. Thank you.