Preprocessor Trickery

[ado at elsie.UUCP]

>	For concatenating strings at preprocessor time, try this:
>
>	#define Ident(xxx) xxx
>
>	#define concat(a,b) Ident(a)b
>
>	It should always work. . .

"Always"?  How about if either "a" or "b" is "__LINE__"?
Try typing this to see what happens:
	cc -E -
	#define Ident(xxx) xxx
	#define concat(a,b) Ident(a)b
	__LINE__
	concat(__LINE__,__LINE__)

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