Re: solution allocation of memory and composite numbers

From	Dr Nick <nospam-4@temporary-address.org.uk>
Newsgroups	comp.lang.c
Subject	Re: solution allocation of memory and composite numbers
References	(9 earlier) <scanf-20141227014317@ram.dialup.fu-berlin.de> <lnfvc1zygk.fsf@nuthaus.mib.org> <s6ut9atugfqbgdgc2e1s1059ps1jndlrf5@4ax.com> <54a2fbca.1024953@news.xs4all.nl> <20141230115350.611@kylheku.com>
Date	2014-12-31 12:24 +0000
Message-ID	<87r3vgdn27.fsf@temporary-address.org.uk> (permalink)

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Kaz Kylheku <kaz@kylheku.com> writes:

> On 2014-12-30, Richard Bos <raltbos@xs4all.nl> wrote:
>> Geoff <geoff@invalid.invalid> wrote:
>>
>>> On Fri, 26 Dec 2014 17:13:47 -0800, Keith Thompson <kst-u@mib.org>
>>> >ram@zedat.fu-berlin.de (Stefan Ram) writes:
>>> >
>>> >> if( 1 == scanf( "%d", &i ))
>>> >
>>> >Personally, I would never advise beginners to write their equality tests
>>> >backwards like that.  There's some risk I might have to read their code
>>> >some day.
>>> 
>>> Some shops require it. There's a very good reason for doing it that
>>> way, namely the = vs == bug in conditionals.
>>
>> That bug is a very good reason _not_ to use this hack. Try it when both
>> operands are variables... introducing a bug in _some_ of your
>
> Huh? When both operands are variables, the conding convention doesn't apply.
> So it provides neither benfit, nor harm.

I disagree.  You have just the same issue with making the flow of the
code match the intent of the tests, with no savings.

If you adopt the "if(3 == counter)" convention, do you also adopt
"if(limit > counter)" rather than "if(counter < limit)"?

If so, you seem to be making your code deliberately less easy to
understand.  And for no benefit in this case.  I believe in Kernigan's
law of Debugging and so don't do that.

If you don't, but you do for the == case, you could end up with a series
of comparison, some of which compare your counter against some constants
and some variables against counter which is just odd.  

What do you do when you have "if(MAXSIZE == OBJECTLIMIT)" and either of
them might just, in some builds, turn out to a variable loaded from a
configuration file but in other builds are numeric constants?

It still seems to me that you need to apply so much thought to this not
to confuse yourself that you'd be better applying the same effort to
checking whether you meant = or ==.  Or even applying a small fraction
of it to configuring your compiler.

Thread

solution allocation of memory and composite numbers Dexterr <dejangru@gmail.com> - 2014-12-24 05:52 -0800
  Re: solution allocation of memory and composite numbers Dexterr <dejangru@gmail.com> - 2014-12-24 05:55 -0800
    Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-24 06:41 -0800
      Re: solution allocation of memory and composite numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-12-24 20:16 +0000
        Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-24 12:39 -0800
          Re: solution allocation of memory and composite numbers Richard Heathfield <invalid@see.sig.invalid> - 2014-12-24 21:22 +0000
            Re: solution allocation of memory and composite numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-12-24 22:33 +0000
              Re: solution allocation of memory and composite numbers Richard Heathfield <invalid@see.sig.invalid> - 2014-12-25 00:54 +0000
                Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-24 18:38 -0800
                Re: solution allocation of memory and composite numbers Vincenzo Mercuri <nomail@yahoo.it> - 2014-12-25 12:07 +0100
                Re: solution allocation of memory and composite numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-12-26 22:05 +0000
                Re: solution allocation of memory and composite numbers BartC <bc@freeuk.com> - 2014-12-26 22:33 +0000
                Re: solution allocation of memory and composite numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-12-27 22:08 +0000
                Re: solution allocation of memory and composite numbers BartC <bc@freeuk.com> - 2014-12-27 23:28 +0000
                Re: solution allocation of memory and composite numbers BartC <bc@freeuk.com> - 2014-12-29 18:34 +0000
                Re: solution allocation of memory and composite numbers raltbos@xs4all.nl (Richard Bos) - 2014-12-30 19:23 +0000
                Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-26 15:43 -0800
                Re: solution allocation of memory and composite numbers Keith Thompson <kst-u@mib.org> - 2014-12-26 15:59 -0800
                Re: solution allocation of memory and composite numbers Vincenzo Mercuri <nomail@yahoo.it> - 2014-12-27 14:45 +0100
                Re: solution allocation of memory and composite numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-12-27 21:55 +0000
                Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-27 14:07 -0800
                Re: solution allocation of memory and composite numbers Vincenzo Mercuri <nomail@yahoo.it> - 2014-12-27 23:44 +0100
                Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-27 15:49 -0800
                Re: solution allocation of memory and composite numbers Keith Thompson <kst-u@mib.org> - 2014-12-27 21:52 -0800
                Re: solution allocation of memory and composite numbers Vincenzo Mercuri <nomail@yahoo.it> - 2014-12-28 15:54 +0100
                Re: solution allocation of memory and composite numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-12-28 00:03 +0000
                Re: solution allocation of memory and composite numbers Keith Thompson <kst-u@mib.org> - 2014-12-26 17:13 -0800
                Re: solution allocation of memory and composite numbers Geoff <geoff@invalid.invalid> - 2014-12-27 10:23 -0800
                Re: solution allocation of memory and composite numbers Stephen Sprunk <stephen@sprunk.org> - 2014-12-27 13:03 -0600
                Re: solution allocation of memory and composite numbers Keith Thompson <kst-u@mib.org> - 2014-12-27 12:24 -0800
                Re: solution allocation of memory and composite numbers Keith Thompson <kst-u@mib.org> - 2014-12-27 12:23 -0800
                Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-27 13:31 -0800
                Re: solution allocation of memory and composite numbers Öö Tiib <ootiib@hot.ee> - 2014-12-27 18:42 -0800
                Re: solution allocation of memory and composite numbers Keith Thompson <kst-u@mib.org> - 2014-12-27 22:07 -0800
                Re: solution allocation of memory and composite numbers raltbos@xs4all.nl (Richard Bos) - 2014-12-30 19:26 +0000
                Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2014-12-30 20:01 +0000
                Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-30 12:18 -0800
                Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2014-12-30 21:15 +0000
                Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-30 13:49 -0800
                Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2014-12-30 22:03 +0000
                Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2014-12-30 23:57 +0000
                Re: solution allocation of memory and composite numbers BartC <bc@freeuk.com> - 2014-12-30 22:35 +0000
                Re: solution allocation of memory and composite numbers Dr Nick <nospam-4@temporary-address.org.uk> - 2014-12-31 12:24 +0000
                Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2014-12-31 17:08 +0000
                Re: solution allocation of memory and composite numbers Dr Nick <nospam-4@temporary-address.org.uk> - 2014-12-31 17:37 +0000
                Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2014-12-30 20:09 +0000
                Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-30 12:24 -0800
                Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2014-12-30 21:28 +0000
                Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-30 13:53 -0800
                Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2015-01-04 02:22 +0000
                Re: solution allocation of memory and composite numbers Xavier Roche <xroche@free.fr.NOSPAM.invalid> - 2014-12-31 13:32 +0100
                Re: solution allocation of memory and composite numbers BartC <bc@freeuk.com> - 2014-12-27 01:37 +0000
                Re: solution allocation of memory and composite numbers raltbos@xs4all.nl (Richard Bos) - 2014-12-27 12:19 +0000
                Re: solution allocation of memory and composite numbers gazelle@shell.xmission.com (Kenny McCormack) - 2014-12-27 14:39 +0000
          Re: solution allocation of memory and composite numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-12-24 22:29 +0000
    Re: solution allocation of memory and composite numbers BartC <bc@freeuk.com> - 2014-12-24 15:05 +0000
  Re: solution allocation of memory and composite numbers Richard Heathfield <invalid@see.sig.invalid> - 2014-12-24 16:55 +0000
    iso646.h Noob <root@127.0.0.1> - 2014-12-25 18:26 +0100
      Re: iso646.h Geoff <geoff@invalid.invalid> - 2014-12-25 18:31 -0800
        Re: iso646.h Noob <root@127.0.0.1> - 2014-12-26 18:23 +0100
      Re: iso646.h Keith Thompson <kst-u@mib.org> - 2014-12-25 21:31 -0800
        Re: iso646.h fir <profesor.fir@gmail.com> - 2014-12-26 09:42 -0800
  Re: solution allocation of memory and composite numbers Barry Schwarz <schwarzb@dqel.com> - 2014-12-24 09:06 -0800
  Re: solution allocation of memory and composite numbers Richard Heathfield <invalid@see.sig.invalid> - 2014-12-24 16:59 +0000
  Re: solution allocation of memory and composite numbers BartC <bc@freeuk.com> - 2014-12-24 17:26 +0000
    Re: solution allocation of memory and composite numbers asetofsymbols@gmail.com - 2014-12-24 11:42 -0800

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