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Re: Which operation is more expensive?(a <= b and a != 0)

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jgk@panix.com (Joe keane) writes:
> In article <87ipimmv7t.fsf@bazspaz.fatphil.org>,
> Phil Carmody  <thefatphil_demunged@yahoo.co.uk> wrote:
> >So you don't like unsigned types for counters then?
> 
> It's typical C to use 'int' unless something else is needed.

Sloppiness is typical too.

Possibly without exception, when the standard library provides an
interface for a function that implies operating over an array of
objects, the number of objects is specified as an unsigned type. 
The sanest internal behaviour for those functions is to have the
same unsigned type as the index controlling the loop.  So there 
are plenty of very common examples of at least implicit unsigned 
counters.

> It's probably an error if the counter comes in negative [or negative if
> it were signed if it's unsigned]

can't parse that, sorry

>, but maybe running zero times is fine.
> 
>     beg = 8;
>     end = 6;
>     for (j = beg; j < end; j++)
> 	...

Ewwwww, integer overflow. Were you attemting to put forward a case
*for* the use of unsigned integers, as at least you'd know that you'd
wrap.

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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Which operation is more expensive?(a <= b and a != 0) Ping Cheu <nospam@nospam.com> - 2012-02-27 21:24 +0000
  Re: Which operation is more expensive?(a <= b and a != 0) James Kuyper <jameskuyper@verizon.net> - 2012-02-27 16:47 -0500
    Re: Which operation is more expensive?(a <= b and a != 0) Michael Angelo Ravera <maravera@prodigy.net> - 2012-03-07 04:23 -0800
  Re: Which operation is more expensive?(a <= b and a != 0) Keith Thompson <kst-u@mib.org> - 2012-02-27 13:54 -0800
    Re: Which operation is more expensive?(a <= b and a != 0) falk@rahul.net (Edward A. Falk) - 2012-02-27 23:47 +0000
  Re: Which operation is more expensive?(a <= b and a != 0) Shao Miller <sha0.miller@gmail.com> - 2012-02-27 16:57 -0500
    Re: Which operation is more expensive?(a <= b and a != 0) Stephen Sprunk <stephen@sprunk.org> - 2012-02-28 13:43 -0600
  Re: Which operation is more expensive?(a <= b and a != 0) Richard Damon <news.x.richarddamon@xoxy.net> - 2012-02-27 16:58 -0500
  Re: Which operation is more expensive?(a <= b and a != 0) Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-02-27 13:55 -0800
    Re: Which operation is more expensive?(a <= b and a != 0) Kenneth Brody <kenbrody@spamcop.net> - 2012-03-03 15:58 -0500
  Re: Which operation is more expensive?(a <= b and a != 0) Keith Thompson <kst-u@mib.org> - 2012-02-27 14:17 -0800
  Re: Which operation is more expensive?(a <= b and a != 0) Barry Schwarz <schwarz45@yahoo.com> - 2012-02-27 14:52 -0800
    Re: Which operation is more expensive?(a <= b and a != 0) Peter Nilsson <airia@acay.com.au> - 2012-02-27 18:16 -0800
      Re: Which operation is more expensive?(a <= b and a != 0) qarnos <darrencubitt@gmail.com> - 2012-02-29 12:20 -0800
      Re: Which operation is more expensive?(a <= b and a != 0) Barry Schwarz <schwarzb@dqel.com> - 2012-03-13 22:07 -0700
  Re: Which operation is more expensive?(a <= b and a != 0) Kaz Kylheku <kaz@kylheku.com> - 2012-02-28 00:56 +0000
  Re: Which operation is more expensive?(a <= b and a != 0) Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2012-02-27 19:18 -0700
    Re: Which operation is more expensive?(a <= b and a != 0) China Blue Sea <chine.bleu@yahoo.com> - 2012-02-27 18:30 -0800
  Re: Which operation is more expensive?(a <= b and a != 0) "BartC" <bc@freeuk.com> - 2012-02-28 13:22 +0000
  Re: Which operation is more expensive?(a <= b and a != 0) Stephen Sprunk <stephen@sprunk.org> - 2012-02-28 13:38 -0600
  Re: Which operation is more expensive?(a <= b and a != 0) jgk@panix.com (Joe keane) - 2012-02-28 22:35 +0000
    Re: Which operation is more expensive?(a <= b and a != 0) Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-03-03 01:36 +0200
      Re: Which operation is more expensive?(a <= b and a != 0) jgk@panix.com (Joe keane) - 2012-03-05 20:03 +0000
        Re: Which operation is more expensive?(a <= b and a != 0) Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-03-12 01:08 +0200
          Re: Which operation is more expensive?(a <= b and a != 0) Harald van Dijk <haraldvdijk@gmail.com> - 2012-03-12 00:05 -0700
            Re: Which operation is more expensive?(a <= b and a != 0) James Kuyper <jameskuyper@verizon.net> - 2012-03-12 08:59 -0400
              Re: Which operation is more expensive?(a <= b and a != 0) gwowen <gwowen@gmail.com> - 2012-03-12 06:24 -0700
                Re: Which operation is more expensive?(a <= b and a != 0) James Kuyper <jameskuyper@verizon.net> - 2012-03-12 10:13 -0400
                Re: Which operation is more expensive?(a <= b and a != 0) Keith Thompson <kst-u@mib.org> - 2012-03-12 10:44 -0700
                Re: Which operation is more expensive?(a <= b and a != 0) Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-03-13 17:12 +0200
          Re: Which operation is more expensive?(a <= b and a != 0) Keith Thompson <kst-u@mib.org> - 2012-03-12 11:20 -0700

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