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Re: #define BYTES *8

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BartC <bc@freeuk.com> wrote:
> JohnF <john@please.see.sig.for.email.com> wrote
>> 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.

Thanks, Bart. I figured it would work because I tested it
and it worked. But I still wanted to double-check becuase
it looked strange, and I'd never used that kind of #define
construction before, nor seen similar stuff used.
   In fact, full disclosure, it would never have occurred
to me except I saw  /mm {2.834646 mul} def  in some
postscript code (who knew there were 2.83 seventy-seconds
of an inch in a mm?).

> 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).

-- 
John Forkosh  ( mailto:  j@f.com  where j=john and f=forkosh )

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#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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