[boost] Re: preprocessor puzzle

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Are you trying to detect 'unsigned char' specifically, or are you ultimately trying to compare strings of identifiers (keywords are identifiers here)?

The IS_UNSIGNED_CHAR() macro is meant to be used in another macro: #define IS_BUILTIN_TYPE(x) BOOST_PP_OR(IS_UNSIGNED_CHAR(x), ...

Here's a more robust implementation of the former:

Thanks, that is extremely helpful, especially because it teaches me more about boost::preprocessor. All the best, Edward