Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
| From | David Brown <david.brown@hesbynett.no> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: Synthetic 'unless' keyword |
| Date | 2016-08-05 13:16 +0200 |
| Organization | A noiseless patient Spider |
| Message-ID | <no1si4$7r5$3@dont-email.me> (permalink) |
| References | <e0gh38F2552U1@mid.uni-berlin.de> <no09cv$p1l$2@jstuckle.eternal-september.org> |
On 04/08/16 22:43, Jerry Stuckle wrote:
> On 8/4/2016 5:44 AM, Jens Thoms Toerring wrote:
>> Hi,
>>
>> everyone uses 'if' probably hundreds of times a day.
>> But in some situations I'd feel that being able to use
>> 'unless' instead, as in the trivial example
>>
>> unless (argc > 1) {
>> fprintf(stderr, "Missing argument(s)\n");
>> return EXIT_FAILURE;
>> }
>>
>> might contribute to the readability of the code. Now,
>> 'unless' isn't a C keyword (as it is in some other
>> languages, e.g. Perl) but it seems easy to use a
>> define like this
>>
>> #define unless(expr) if (!(expr))
>>
>> What possibly could go wrong (except that 'unless' may
>> be used as a variable name somewhere and that editors
>> with syntax highlighting won't recognize it)? Or would
>> it be to "alien" to most C programmers?
>>
>> Best regards, Jens
>>
>
> I'm going to differ with most of the others here. I think the could be
> a useful addition. It could simplify a complex if condition.
>
> Many times I've duplicated something like this with;
>
> if (complex_condition) {
> ;
> }
> else {
> do something here;
> }
>
> Which has the same results, but I don't think it quite as clear.
>
I've done that occasionally, if it fitted a pattern with existing code.
I put a comment on the "blank" line to make it clear that it is
intentional.
Back to comp.lang.c | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
Synthetic 'unless' keyword jt@toerring.de (Jens Thoms Toerring) - 2016-08-04 09:44 +0000
Re: Synthetic 'unless' keyword David Brown <david.brown@hesbynett.no> - 2016-08-04 12:21 +0200
Re: Synthetic 'unless' keyword Mark Storkamp <mstorkamp@yahoo.com> - 2016-08-04 07:01 -0500
Re: Synthetic 'unless' keyword bert <bert.hutchings@btinternet.com> - 2016-08-04 05:42 -0700
Re: Synthetic 'unless' keyword Keith Thompson <kst-u@mib.org> - 2016-08-04 08:45 -0700
Re: Synthetic 'unless' keyword Philip Lantz <prl@canterey.us> - 2016-08-04 21:55 -0700
Re: Synthetic 'unless' keyword BartC <bc@freeuk.com> - 2016-08-05 10:08 +0100
Re: Synthetic 'unless' keyword Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-08-05 01:17 -0700
Re: Synthetic 'unless' keyword BartC <bc@freeuk.com> - 2016-08-05 10:01 +0100
Re: Synthetic 'unless' keyword Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-08-05 04:34 -0700
Re: Synthetic 'unless' keyword Mark Storkamp <mstorkamp@yahoo.com> - 2016-08-05 09:37 -0500
Re: Synthetic 'unless' keyword Malcolm McLean <malcolm.mclean5@btinternet.com> - 2016-08-06 02:28 -0700
Re: Synthetic 'unless' keyword jt@toerring.de (Jens Thoms Toerring) - 2016-08-04 13:38 +0000
Re: Synthetic 'unless' keyword BartC <bc@freeuk.com> - 2016-08-04 15:04 +0100
Re: Synthetic 'unless' keyword mark.bluemel@gmail.com - 2016-08-04 07:06 -0700
Re: Synthetic 'unless' keyword Keith Thompson <kst-u@mib.org> - 2016-08-04 08:52 -0700
Re: Synthetic 'unless' keyword supercat@casperkitty.com - 2016-08-04 09:45 -0700
Re: Synthetic 'unless' keyword Keith Thompson <kst-u@mib.org> - 2016-08-04 10:23 -0700
Re: Synthetic 'unless' keyword Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-08-04 19:39 +0100
Re: Synthetic 'unless' keyword supercat@casperkitty.com - 2016-08-04 12:02 -0700
Re: Synthetic 'unless' keyword Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-08-04 20:33 +0100
Re: Synthetic 'unless' keyword BartC <bc@freeuk.com> - 2016-08-04 20:42 +0100
Re: Synthetic 'unless' keyword David Brown <david.brown@hesbynett.no> - 2016-08-05 13:14 +0200
Re: Synthetic 'unless' keyword Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-08-05 12:41 +0100
Re: Synthetic 'unless' keyword mark.bluemel@gmail.com - 2016-08-05 00:53 -0700
Re: Synthetic 'unless' keyword Jerry Stuckle <jstucklex@attglobal.net> - 2016-08-04 16:43 -0400
Re: Synthetic 'unless' keyword David Brown <david.brown@hesbynett.no> - 2016-08-05 13:16 +0200
Re: Synthetic 'unless' keyword jt@toerring.de (Jens Thoms Toerring) - 2016-08-04 23:16 +0000
Re: Synthetic 'unless' keyword Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-08-05 00:35 +0100
Re: Synthetic 'unless' keyword Tim Rentsch <txr@alumni.caltech.edu> - 2016-08-04 20:13 -0700
Re: Synthetic 'unless' keyword Tim Rentsch <txr@alumni.caltech.edu> - 2016-08-05 04:57 -0700
Re: Synthetic 'unless' keyword BartC <bc@freeuk.com> - 2016-08-05 13:15 +0100
Re: Synthetic 'unless' keyword Tim Rentsch <txr@alumni.caltech.edu> - 2016-08-18 08:11 -0700
Re: Synthetic 'unless' keyword BartC <bc@freeuk.com> - 2016-08-18 16:36 +0100
Re: Synthetic 'unless' keyword supercat@casperkitty.com - 2016-08-18 10:20 -0700
Re: Synthetic 'unless' keyword Paul N <gw7rib@aol.com> - 2016-08-07 12:56 -0700
csiph-web