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| From | Dr Nick <nospam-4@temporary-address.org.uk> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: solution allocation of memory and composite numbers |
| References | (11 earlier) <s6ut9atugfqbgdgc2e1s1059ps1jndlrf5@4ax.com> <54a2fbca.1024953@news.xs4all.nl> <20141230115350.611@kylheku.com> <87r3vgdn27.fsf@temporary-address.org.uk> <20141231085746.522@kylheku.com> |
| Date | 2014-12-31 17:37 +0000 |
| Message-ID | <871tnfen4w.fsf@temporary-address.org.uk> (permalink) |
Kaz Kylheku <kaz@kylheku.com> writes:
> On 2014-12-31, Dr Nick <nospam-4@temporary-address.org.uk> wrote:
>> 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)"?
>
> No, because in this case, flipping the two expressions requires
> a change of operator; the operator is not symmetric.
>
> Whereas if a == b, then b == a, it is not the case that if a < b then b < a.
>
> Inequality has direction, and a mixup in the understanding of the direction
> has consequences, whereas equality is directionless, so it has no such
> issue.
>
> Also, < is not easily misspelled into some similar operator that
> clobbers storage locations.
But that then leads you to absurdities like this:
#include "filethatdefinesomeconstants.h"
if (a <= LOWERVALUE)
dosomething();
if (a > LOWERVALUE && a < MAXVALUE)
dosomethingelse();
if (MAXVALUE == a)
doanotherthing();
I'd accept any number of debugging problems not to code like this -
because I genuinely believe that examples like this genuinely make the
code harder to understand.
Add modern compilers and there's no justification for it.
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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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