Question about ANSI preprocessor

Larry Jones scjones at sdrc.UUCP
Fri Sep 29 08:30:57 AEST 1989


In article <10879 at riks.csl.sony.co.jp>, diamond at csl.sony.co.jp (Norman Diamond) writes:
> According to the ANSI standard, does the following code cause
> expansion of the preprocessor macro "huh"?
> 
> #define huh(x) (abc + (x))
> 
> y = huh
> #if 0
> 	, a, lot, of, garbage
> #endif
> (z);

No.  Section 3.8.3 (Macro replacement) talks about function-like
macros and says:

	Each subsequent instance of the function-like macro name
	followed by a ( as the next preprocessing token
	introduces the sequence of proprocessing tokens that is
	replaced by the replacement list in the definition (an
	invocation of the macro).

In this case, the preprocessing token following the macro name is
"#" rather than "(", so it is not eligable for expansion.
----
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