Re: #define BYTES *8

From	"BartC" <bc@freeuk.com>
Newsgroups	comp.lang.c
Subject	Re: #define BYTES *8
Date	2012-08-28 12:34 +0100
Organization	A noiseless patient Spider
Message-ID	<k1iacc$ad$1@dont-email.me> (permalink)
References	<k1hssn$c4o$1@reader1.panix.com> <lnwr0jza09.fsf@nuthaus.mib.org> <k1i2i2$6k6$1@reader1.panix.com>

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"JohnF" <john@please.see.sig.for.email.com> wrote in message
news:k1i2i2$6k6$1@reader1.panix.com...

> My bad. The actual app involves physical units. I just used
> bits/bytes as an example for the post. Moreover, the actual
> program is user-modifiable at compile time by way of an
> #include "userformulas.h" in the middle of the code (not as
> a header) containing stuff like length=10 feet; width=3 inches;
> height=4 meters; etc;

I use the same thing elsewhere:

 x = 3m+50cm

so x ends up as 3500 when the basic unit is mm (m scales by 1000, and cm by
10).

So it sounds reasonable enough and using #define as you have sounds like the
closest you might get in C source code.

However:

o I only use such a suffix after a constant
o It only applies to the immediately preceding constant

So your 2+2 BYTES example elsewhere would need to be written as 2 BYTES + 2
BYTES, which makes more sense anyway.

> The only question I'm asking
> is about any straightforward semantic problems arising from
> the funky-looking syntactic construction.

Without proper language support, your macro could be used in ways that were
not intended (2 BYTES BYTES BYTES for example).

-- 
Bartc

Thread

#define BYTES *8 JohnF <john@please.see.sig.for.email.com> - 2012-08-28 07:44 +0000
  Re: #define BYTES *8 Mark Bluemel <mark_bluemel@pobox.com> - 2012-08-28 09:07 +0100
  Re: #define BYTES *8 Keith Thompson <kst-u@mib.org> - 2012-08-28 01:38 -0700
    Re: #define BYTES *8 JohnF <john@please.see.sig.for.email.com> - 2012-08-28 09:21 +0000
      Re: #define BYTES *8 "BartC" <bc@freeuk.com> - 2012-08-28 12:34 +0100
        Re: #define BYTES *8 JohnF <john@please.see.sig.for.email.com> - 2012-08-28 12:23 +0000
    Re: #define BYTES *8 Kenneth Brody <kenbrody@spamcop.net> - 2012-08-29 11:10 -0400
      Re: #define BYTES *8 Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-29 11:36 -0400
        Re: #define BYTES *8 Adrian Ratnapala <raka@scooter.fritz.box> - 2012-08-30 04:01 +0000
        Re: #define BYTES *8 Kenneth Brody <kenbrody@spamcop.net> - 2012-08-30 19:08 -0400
          <OT> Re: #define BYTES *8 Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-30 21:30 -0400
            Re: <OT> Re: #define BYTES *8 Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-08-31 02:49 +0100
              Re: <OT> Re: #define BYTES *8 JohnF <john@please.see.sig.for.email.com> - 2012-08-31 08:32 +0000
                Re: <OT> Re: #define BYTES *8 88888 Dihedral <dihedral88888@googlemail.com> - 2012-08-31 03:55 -0700
              Re: <OT> Re: #define BYTES *8 "BartC" <bc@freeuk.com> - 2012-08-31 10:58 +0100
                Re: <OT> Re: #define BYTES *8 Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-08-31 11:53 +0100
                Re: <OT> Re: #define BYTES *8 "BartC" <bc@freeuk.com> - 2012-08-31 12:39 +0100
                Re: <OT> Re: #define BYTES *8 Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-08-31 15:35 +0100
                Re: <OT> Re: #define BYTES *8 "BartC" <bc@freeuk.com> - 2012-08-31 19:15 +0100
                Re: <OT> Re: #define BYTES *8 Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-08-31 14:39 -0400
            Re: <OT> Re: #define BYTES *8 Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-09-06 15:14 +0300
  Re: #define BYTES *8 "Scott Fluhrer" <sfluhrer@ix.netcom.com> - 2012-08-28 12:24 -0400
    Re: #define BYTES *8 "BartC" <bc@freeuk.com> - 2012-08-28 17:44 +0100
    Re: #define BYTES *8 Keith Thompson <kst-u@mib.org> - 2012-08-28 14:42 -0700
  Re: #define BYTES *8 pete <pfiland@mindspring.com> - 2012-08-28 23:47 -0400
  Re: #define BYTES *8 Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2012-08-29 22:20 -0600
  Re: #define BYTES *8 John Bode <jfbode1029@gmail.com> - 2012-09-06 15:32 -0700
    Re: #define BYTES *8 pete <pfiland@mindspring.com> - 2012-09-06 20:58 -0400
      Re: #define BYTES *8 Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-09-06 21:13 -0400
      Re: #define BYTES *8 Öö Tiib <ootiib@hot.ee> - 2012-09-07 03:00 -0700
        Re: #define BYTES *8 pete <pfiland@mindspring.com> - 2012-09-08 10:00 -0400
    Re: #define BYTES *8 "BartC" <bc@freeuk.com> - 2012-09-07 02:22 +0100
      Re: #define BYTES *8 John Bode <jfbode1029@gmail.com> - 2012-09-07 05:55 -0700
  Re: #define BYTES *8 Tim Rentsch <txr@alumni.caltech.edu> - 2012-09-07 14:20 -0700

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