Path: utzoo!attcan!uunet!dino!ux1.cso.uiuc.edu!brutus.cs.uiuc.edu!wuarchive!wums2!bethge
From: bethge@wums.wustl.edu
Newsgroups: comp.lang.c
Subject: Re: Re^2: Why nested comments not allowed?
Message-ID: <2037.25e266bf@wums.wustl.edu>
Date: 21 Feb 90 16:00:31 GMT
References: <236100027@prism> <7330017@hpcllak.HP.COM> <1990Feb19.143619.17663@uncecs.edu> <1975.25e0048c@wums.wustl.edu> <1990Feb20.165353.14212@uncecs.edu>
Lines: 41

In article <1990Feb20.165353.14212@uncecs.edu>, utoddl@uncecs.edu
(Todd M. Lewis) writes:
> You have quite precisely missed my point.  It was even in quotes.  Briefly:
>    1)  "comment out a section..."      Use comments.
>    2)  "compile if x {not} defined"    Use #if{n}def/#endif.
> See the difference?  In particular, I did not say that nested comments are
> the better way to suppress the compilation of a section of code. If it's a
> comment it isn't code!  The notion of conditionally compiling comments is
> a bit off the mark, IMHO.  Comments are never compiled--nothing conditional
> about that.  Lexed or parsed maybe, but not compiled.
>   It isn't a religious issue. It is a semantic issue--on two levels, no less.
> On the lower level, what I said is not what you thought I meant.  On the
> higher level, #ifdef/#endif and nested comments are not the same although
> the end result may be the same.

OK, I am not understanding you.  Can you enlighten me?  My question is,
*why* do you want nested comments?  I asked this question in a previous
posting, to which no one responded.  As I said then, the only use I can
think  of  is  to  suppress  the  compilation  of  a  section  of  code
(containing comments), by turning it into a comment.  This  is  what  I
understand to be the meaning of the phrase "comment out a section...".

I know that the *mechanisms* of #ifdef/#endif and nested  comments  are
different.   But  if the *purpose* is the same, and the *end result* is
the same, why are both needed?  Do you object the the introduction of a
bogus undefined identifier, as in
        #ifdef YES_COMPILE_THIS_HERE_BIT_OF_HACKWORK
        . . .
        #endif
or what?

Or is there really some other use for nested comments?  If there is,  I
don't want to remain ignorant of it.

No sarcasm intended.  I really am seeking enlightenment.

_______________________________________________________________________
Paul H. Bethge                                    bethge@wums.wustl.edu
Biochemistry, Box 8231                               bethge@wums.bitnet
Washington University
St. Louis, MO 63110                                        314-362-3354