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Using va_arg for variable params in a macro

Posted on 2001-06-19
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Last Modified: 2008-01-16
A colleague wrote me:

"I recently ran across some info about some new C standard allowing a variable number of arguments in a macro via the macro __VA_ARGS__. Does MS C++ allow this in macro's?"

I have never heard of __VA_ARGS__ but found a proposal for it in a document dated 1999, with no followup.  Any info out there?

Is there a way to use the va_arg macro to allow a variable number of parameters in a macro?
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Question by:appleby
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IainHere earned 75 total points
ID: 6206832
__VA_ARGS__ is part of the C99 standard.  It is certainly not supported by VC++ 6.0, along with most of the other additions to the language made by C99.

For example, try compiling the following [legal under C99]:

#define DoLogFile(...) fprintf(stderr, __VA_ARGS__)
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by:appleby
ID: 6206860
Ok, thanks!
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