🚀 go-pugleaf

In article <4es8rp$98n@usenet.pa.dec.com> diamond@tko.dec.com (Norman
Diamond) writes: 
<snip>
   >>Is the following program legal?
   >>#define foo(unused)
   >>#define bar(x,y)
   >>foo(bar(1))

   >I read it as being legal.

   Mr. Bhattacharya, I am shocked.

   >>Excerpt from "6.8.3.1 Argument substitution"
   >>  After the arguments for the invocation of a function-like macro have
   >>  been identified, argument substitution takes place. A parameter in the
   >>  replacment list, ..., is replaced by the corresponding argument after
   >>  all macros contained therein have been expanded. Before being
   >>  substituted, each argument's preprocessing tokens are completely macro
   >>  replaced ... .

   >You gave the reason :-) The quoted text seems to imply the following order:
   >  1) Identify parameters
   [...]

   I think there's a preceding order as well:
      0) constraints checked, including ANSI Classic section 3.8.3, page 90
	 lines 14 to 15:  "The number of arguments in an invocation of a
	 function-like macro shall agree with the number of parameters in
	 the macro definition, and [...]"

I think the important question is whether bar is ever invoked here. I
read it as legal because I interpreted the wording as macros in
parameters are invoked only if they appear in the replacement list not
preceded by # or ## and not followed by ##; or if they are otherwise
invoked during rescanning. 

Cheers
Tanmoy
--
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