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Re: Preprocessor automation to define/declare array of strings

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Ben Bacarisse <ben.usenet@bsb.me.uk> writes:
> pozzugno@gmail.com (pozz) writes:
> <snip>
> > And what if my "very old microcontroller" compiler doesn't support
> > variadic macros?
> 
> In the common include write this:
> 
>   STRINGLIST(strlist_month) { "Jan", "Feb", "Mar" } EOL));
> 
> and so on for each list.  To get the .c file use:
> 
>   #define KILL(x)
>   #define STRINGLIST(name) const char *name[] =
>   #define EOL KILL((
> 
> and to get the .h file use:
> 
>   #define KILL(x)
>   #define STRINGLIST(name) extern const char *name[] KILL((
>   #define EOL
> 
> The "KILL" macro is the same.

I find that a little perverse with the parentheses divorced from their partners, 
but not actually wrong. Perhaps "clever" is the most appropriate way of expressing
my worries about it.


For variety, I'm sure I encountered something like this in the past:

In one location define:

#define INTRO(name) const char *name[] = {
#define ELEMENT(s) s,
#define OUTRO };

In a different location define:

#define INTRO(name) extern const char *name[];
#define ELEMENT(s)
#define OUTRO

Which permits you do have files such as

INTRO(strlist_month)
ELEMENT("Jan")
ELEMENT("Feb")
...
OUTRO


I think when I saw it, the first thing that went through my mind was 

#define INTRO(name) extern const char *name[0
#define ELEMENT(s) +1
#define OUTRO ]

such that the clients can know the size of the array, which means you don't need a
sentinal at the end, or a redundantly-provided source for that information.
However, I've not ever really needed to use the technique. I offer it just as 
a new way of approaching the problem.

Phil
-- 
> I'd argue that there is much evidence for the existence of a God.
Pics or it didn't happen.
-- Tom (/. uid 822)

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Preprocessor automation to define/declare array of strings pozzugno@gmail.com (pozz) - 2012-08-06 16:23 +0200
  Re: Preprocessor automation to define/declare array of strings Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-06 10:51 -0400
    Re: Preprocessor automation to define/declare array of strings Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-06 11:01 -0400
    Re: Preprocessor automation to define/declare array of strings pozzugno@gmail.com (pozz) - 2012-08-06 17:10 +0200
      Re: Preprocessor automation to define/declare array of strings Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-06 12:51 -0400
      Re: Preprocessor automation to define/declare array of strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-08-06 18:27 +0100
        Re: Preprocessor automation to define/declare array of strings Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-08-10 11:35 +0300
          OT (Re: Preprocessor automation to define/declare array of strings) Mark Bluemel <mark_bluemel@pobox.com> - 2012-08-10 09:56 +0100
            Re: OT (Re: Preprocessor automation to define/declare array of strings) Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-08-12 02:38 +0300
          Re: Preprocessor automation to define/declare array of strings Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-08-10 12:45 +0100
      Re: Preprocessor automation to define/declare array of strings Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-08-07 00:16 -0700
        Re: Preprocessor automation to define/declare array of strings Tim Rentsch <txr@alumni.caltech.edu> - 2012-09-07 13:49 -0700
  Re: Preprocessor automation to define/declare array of strings Ike Naar <ike@faeroes.freeshell.org> - 2012-08-06 14:55 +0000
  Re: Preprocessor automation to define/declare array of strings Jorgen Grahn <grahn+nntp@snipabacken.se> - 2012-08-11 06:09 +0000

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