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Groups > comp.lang.c > #149810
| From | Ben Bacarisse <ben.usenet@bsb.me.uk> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: Coding style for small if statements |
| Date | 2020-02-07 01:26 +0000 |
| Organization | A noiseless patient Spider |
| Message-ID | <874kw3nq6s.fsf@bsb.me.uk> (permalink) |
| References | <20200131234613.59047e037939ceb549b8e6d6@gmail.com> <65de5d07-838a-4a5f-bd70-b8a263fc61d6@googlegroups.com> <87imkkobdm.fsf@bsb.me.uk> <726b2209-ca7e-40fe-b429-fbc062f5b6bd@googlegroups.com> |
John Bode <jfbode1029@gmail.com> writes:
> On Wednesday, February 5, 2020 at 5:36:14 PM UTC-6, Ben Bacarisse wrote:
>> John Bode <jfbode1029@gmail.com> writes:
>>
>> > On Friday, January 31, 2020 at 2:46:22 PM UTC-6, Anton Shepelev wrote:
>> >> Hello, all
>> >>
>> >> What do you think about the formatting and readability of
>> >> the following code of mine from a display-setup function for
>> >> the DOSBox emulator:
>> >>
>> >> if( dblh != dblw )
>> >> if( dblh ) gfx_flags |= GFX_DBL_H; else
>> >> gfx_flags |= GFX_DBL_W;
>> >>
>> >
>> > Gah. That merits a paddlin'.
>> >
>> > My personal rules:
>> >
>> > 1. Only omit braces for the innermost if (when applicable), and only if it does not have
>> > an associated else;
>> > 2. Braces and else go on their own lines;
>> > 3. Braces line up with the if and else;
>> >
>> > To wit:
>> >
>> > if ( dblh != dblw )
>> > {
>> > if ( dblh )
>> > {
>> > gfx_flags |= GFX_DBL_H;
>> > }
>> > else
>> > {
>> > gfx_flags |= GFX_DBL_W;
>> > }
>> > }
>> >
>> > Unambiguous.
>>
>> So was the original!
>
> Not according to whomever reviewed Anton's code. At a glance, it looks like
>
> gfx_flags |= GFX_DBL_W;
>
> belongs to the "if (dblh)" branch. The first time I scanned the code
> I missed the "else" keyword altogether. That's why I put "else" on
> its own line, always.
You are using ambiguous to mean "can be misread". I see, and I agree.
I am sure there are people who can misread almost any code but that
would turn into a discussion of degree. I thought you meant something
else by "unambiguous".
>> > It's clear which if the else belongs to, it's clear which branch is taken
>> > based on the conditions, etc.
>
> Not to my middle-aged eyes.
Mine are old-aged and I need strong reading glasses, but I can see the
else quite clearly. It's not easy to code for other people's eyes. I
don't think I've come across anyone saying the they need the else on a
line by itself in order to see it clearly.
>> How could it not be clear which "if" the "else" is part of? Now I can
>> imagine some people who might not know (which is not quite the same
>> thing), but I really don't want such a person maintaining /any/ code.
>>
>> You hear a lot about the crisis in software (or you used to -- maybe
>> it's fixed now!). There's no hope, though, if software is being altered
>> by people who don't understand the original code as posted.
>>
>
> On an average day I'm helping support troubleshoot multiple issues,
> clearing at least one bug, writing up deployment tickets, going to
> meetings, and writing a new interface. On top of all that, my eyes
> are almost 55 years old and don't work so well anymore. If I have to
> spend more than a few seconds trying to parse out what you *meant*
> based on some dodgy formatting, I am going to kick it back to you and
> tell you to make it explicit.
The boss is always right!
>> > You won't introduce a bug if you decide to add a logging
>> > statement to either branch.
>>
>> That's not really what you mean. You mean it's easier to do so, or at
>> least less error prone in the face of people who just type code without
>> knowing what the language. (You can only add a statement to either
>> branch if you add {}s.)
>
> You can add statements to either branch without adding the {}s,
We are just disagreeing about words. I don't think that's going to be
productive other than maybe highlighting how our words can be
misunderstood.
> your code just won't
> work properly. Nothing's physically stopping you from writing
>
> if ( a )
> do_something();
> do_another_thing();
This change (as I am sure you know) has not "added statements to either
branch". I just think you could be be clearer in your wording. We both
know what's happening in the code.
> It's just that if you're expecting do_another_thing() only to execute
> when a is true, then you're going to be bitterly disappointed.
>
> It happens. It's happened a *lot* over the last 30 years.
This may be why there is such a crisis in software development. I can't
imagine anyone I've worked with doing this (i.e. just adding a line
thining it's goinf to be part of the "if"), but maybe I've just been
lucky. Maybe companies have no choice but to hire people to work on C
code who might just type that line above, thinking it's adding code to a
branch of the if.
What's more, you are suggesting that code errors of this sort frequently
survive long enough for someone like you to see them. Whilst C programs
can have subtle errors that go uncaught for some time, your people
should have a testing regime in place so that basic errors of logic get
caught immediately.
> So I'm going to tell you to use
> braces everywhere all the time. There's one case where I *won't* kick back code
> that doesn't use braces for an "if" branch, but otherwise they need to be there.
>
>>
>> > It sacrifices some vertical space (and a little visual clutter), but
>> > nobody's going to come tracking you down later to ask what the hell
>> > you meant.
>>
>> It would be simpler to track down someone who knows C's syntax first.
>>
>
> Yeah, suppose the code was formatted as
>
> if ( a )
> if ( b )
> do_something();
> else
> do_something_else();
>
> What did I mean to do? Not "what does this syntax mean", but what was
> my *intent*? How would you tell?
Why would I care? (I am being serious.) If the code is failing some
tests, I will look at what the code actually does whilst trying as hard
as possible to ignore what you might have meant. Nothing else matters.
If the code is passing all the tests, I'd probably leave it alone. If,
in the case of apparently correct code, I were to speculate on what you
meant, it would be both wise (and polite!) to assume you meant exactly
what the syntax says.
> This isn't a syntax issue. This is a clarity issue. Using braces
> everywhere all the time makes your intent clear. Consistent
> formatting with clearly indicated scope boundaries makes your intent
> clear.
Why do you care about the intent? What matters is what the code
actually does. (There is another kind of clarity that relates to
readability but that does not seem to be what you are stressing here.)
> If your code is not clear *at a glance*, then I'm not going to waste
> my limited time with it.
Of course. Neither of us would want that!
--
Ben.
Back to comp.lang.c | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
Coding style for small if statements Anton Shepelev <anton.txt@gmail.com> - 2020-01-31 23:46 +0300
Re: Coding style for small if statements Anton Shepelev <anton.txt@gmail.com> - 2020-01-31 23:54 +0300
Re: Coding style for small if statements Les Cargill <lcargill99@comcast.com> - 2020-01-31 19:13 -0600
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-22 07:52 -0800
Re: Coding style for small if statements Anton Shepelev <anton.txt@gmail.com> - 2020-02-01 00:06 +0300
Re: Coding style for small if statements mathog <dmathog@gmail.com> - 2020-02-28 10:20 -0800
Re: Coding style for small if statements Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2020-01-31 16:28 -0500
Re: Coding style for small if statements donalhambra@gmail.com - 2020-02-01 04:55 -0800
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-01 17:16 +0000
Re: Coding style for small if statements luser droog <luser.droog@gmail.com> - 2020-02-02 11:03 -0800
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-03 02:20 +0000
Re: Coding style for small if statements Bonita Montero <Bonita.Montero@gmail.com> - 2020-02-03 05:17 +0100
Re: Coding style for small if statements chad <cdalten@gmail.com> - 2020-02-03 04:07 -0800
Re: Coding style for small if statements luser droog <luser.droog@gmail.com> - 2020-02-03 12:59 -0800
Re: Coding style for small if statements chad <cdalten@gmail.com> - 2020-02-03 20:54 -0800
Re: Coding style for small if statements nobody@example.org (Scott) - 2020-02-01 16:44 +0000
Re: Coding style for small if statements already5chosen@yahoo.com - 2020-02-02 04:40 -0800
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-02 15:47 +0100
Re: Coding style for small if statements Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-02-03 23:56 +0000
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-16 05:34 -0800
Re: Coding style for small if statements Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-02-16 16:17 +0000
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-22 08:28 -0800
Re: Coding style for small if statements skybuck2000@hotmail.com - 2020-02-03 21:52 -0800
Re: Coding style for small if statements skybuck2000@hotmail.com - 2020-02-03 22:07 -0800
Re: Coding style for small if statements skybuck2000@hotmail.com - 2020-02-03 22:22 -0800
Re: Coding style for small if statements skybuck2000@hotmail.com - 2020-02-03 22:25 -0800
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-05 02:35 +0000
Re: Coding style for small if statements James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-02-04 20:20 -0800
Re: Coding style for small if statements James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-02-05 01:04 -0500
Re: Coding style for small if statements James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-02-05 01:05 -0500
Re: Coding style for small if statements John Bode <jfbode1029@gmail.com> - 2020-02-05 12:50 -0800
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-05 23:36 +0000
Re: Coding style for small if statements John Bode <jfbode1029@gmail.com> - 2020-02-06 15:01 -0800
Re: Coding style for small if statements Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-02-06 15:43 -0800
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-07 11:02 +0100
Re: Coding style for small if statements scott@slp53.sl.home (Scott Lurndal) - 2020-02-07 15:24 +0000
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-07 23:03 +0000
Re: Coding style for small if statements scott@slp53.sl.home (Scott Lurndal) - 2020-02-07 23:59 +0000
Re: Coding style for small if statements Bart <bc@freeuk.com> - 2020-02-08 00:16 +0000
Re: Coding style for small if statements scott@slp53.sl.home (Scott Lurndal) - 2020-02-08 02:26 +0000
Re: Coding style for small if statements Les Cargill <lcargill99@comcast.com> - 2020-02-08 17:07 -0600
Re: Coding style for small if statements Bart <bc@freeuk.com> - 2020-02-08 23:17 +0000
Re: Coding style for small if statements Les Cargill <lcargill99@comcast.com> - 2020-02-08 18:32 -0600
Re: Coding style for small if statements Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2020-02-09 09:32 -0800
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-16 07:10 -0800
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-07 01:26 +0000
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-07 11:30 +0100
Re: Coding style for small if statements chad <cdalten@gmail.com> - 2020-02-07 05:36 -0800
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-07 23:36 +0000
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-08 17:20 +0100
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-09 02:07 +0000
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-09 13:01 +0100
Re: Coding style for small if statements Bart <bc@freeuk.com> - 2020-02-09 13:26 +0000
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-09 15:53 +0000
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-09 17:03 +0100
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-09 15:35 +0000
Re: Coding style for small if statements Manfred <noname@add.invalid> - 2020-02-09 18:07 +0100
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-09 21:17 +0000
Pre- and post- conditions (was Re: Coding style for small if statements) Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-02-11 07:19 +0000
Re: Pre- and post- conditions (was Re: Coding style for small if statements) Öö Tiib <ootiib@hot.ee> - 2020-02-10 23:40 -0800
Re: Pre- and post- conditions (was Re: Coding style for small if statements) Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-02-12 12:24 +0000
Re: Pre- and post- conditions (was Re: Coding style for small if statements) Bart <bc@freeuk.com> - 2020-02-11 11:30 +0000
Re: Pre- and post- conditions (was Re: Coding style for small if statements) Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2020-02-11 09:41 -0700
Re: Pre- and post- conditions (was Re: Coding style for small if statements) James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-02-12 08:12 -0500
Re: Pre- and post- conditions (was Re: Coding style for small if statements) Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-02-14 21:18 +0000
Re: Pre- and post- conditions (was Re: Coding style for small if statements) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-22 00:01 -0800
Re: Pre- and post- conditions (was Re: Coding style for small if statements) James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-02-22 05:22 -0800
Re: Pre- and post- conditions (was Re: Coding style for small if statements) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-04-02 07:57 -0700
Re: Pre- and post- conditions (was Re: Coding style for small if statements) James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-04-02 08:28 -0700
Re: Pre- and post- conditions (was Re: Coding style for small if statements) jadill33@gmail.com - 2020-02-12 07:56 -0800
Re: Pre- and post- conditions (was Re: Coding style for small if statements) chad <cdalten@gmail.com> - 2020-02-12 08:57 -0800
Re: Pre- and post- conditions (was Re: Coding style for small if statements) Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-02-14 21:31 +0000
Re: Pre- and post- conditions (was Re: Coding style for small if statements) jadill33@gmail.com - 2020-02-14 14:10 -0800
Re: Pre- and post- conditions (was Re: Coding style for small if statements) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-15 03:06 +0000
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-09 19:45 +0100
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-09 21:50 +0000
Re: Coding style for small if statements Bart <bc@freeuk.com> - 2020-02-09 22:51 +0000
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-10 01:39 +0000
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-10 09:55 +0100
Re: Coding style for small if statements Bart <bc@freeuk.com> - 2020-02-10 11:07 +0000
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-10 12:48 +0100
Re: Coding style for small if statements Bart <bc@freeuk.com> - 2020-02-10 13:13 +0000
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-10 15:15 +0100
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-10 15:46 +0000
Re: Coding style for small if statements James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-02-09 18:18 -0800
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-10 09:12 +0100
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-10 14:51 +0000
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-10 16:19 +0000
Re: Coding style for small if statements Bart <bc@freeuk.com> - 2020-02-09 21:00 +0000
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-09 21:29 +0000
Re: Coding style for small if statements luser droog <luser.droog@gmail.com> - 2020-02-09 17:14 -0800
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-09 21:15 +0000
Re: Coding style for small if statements James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-02-09 18:43 -0500
Re: Coding style for small if statements Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-02-10 01:25 +0000
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-22 01:19 -0800
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-16 05:43 -0800
Re: Coding style for small if statements Bart <bc@freeuk.com> - 2020-02-16 14:01 +0000
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-22 08:34 -0800
Re: Coding style for small if statements Guillaume <message@bottle.org> - 2020-02-07 15:25 +0100
Re: Coding style for small if statements Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2020-02-07 07:22 -0800
Re: Coding style for small if statements Anton Shepelev <anton.txt@g{oogle}mail.com> - 2020-02-14 15:21 +0300
Re: Coding style for small if statements Bart <bc@freeuk.com> - 2020-02-14 13:35 +0000
Re: Coding style for small if statements Guillaume <message@bottle.org> - 2020-02-14 14:43 +0100
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-15 12:08 +0100
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-20 10:10 -0800
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-20 19:58 +0100
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-16 05:55 -0800
Re: Coding style for small if statements scott@slp53.sl.home (Scott Lurndal) - 2020-02-07 15:26 +0000
Re: Coding style for small if statements luser droog <luser.droog@gmail.com> - 2020-02-07 17:47 -0800
Re: Coding style for small if statements jadill33@gmail.com - 2020-02-10 07:09 -0800
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-16 06:30 -0800
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-16 16:14 +0100
Re: Coding style for small if statements Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-02-16 16:40 +0000
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-16 17:48 +0100
Re: Coding style for small if statements Robert Wessel <robertwessel2@yahoo.com> - 2020-02-16 17:14 -0600
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-03-30 00:27 -0700
Re: Coding style for small if statements Ike Naar <ike@sdf.lonestar.org> - 2020-02-16 18:39 +0000
Re: Coding style for small if statements Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-02-16 20:37 +0000
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-02-17 09:09 +0100
Re: Coding style for small if statements Öö Tiib <ootiib@hot.ee> - 2020-02-17 05:32 -0800
Re: Coding style for small if statements scott@slp53.sl.home (Scott Lurndal) - 2020-02-17 18:07 +0000
Re: Coding style for small if statements Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-02-17 23:48 +0000
Re: Coding style for small if statements Richard Damon <Richard@Damon-Family.org> - 2020-02-17 20:40 -0500
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-23 10:14 -0800
Re: Coding style for small if statements Ike Naar <ike@iceland.freeshell.org> - 2020-02-23 20:16 +0000
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-03-29 18:56 -0700
Re: Coding style for small if statements Ike Naar <ike@sdf.lonestar.org> - 2020-03-30 06:07 +0000
Re: Coding style for small if statements Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-03-30 06:45 +0000
Re: Coding style for small if statements David Brown <david.brown@hesbynett.no> - 2020-03-30 10:50 +0200
Re: Coding style for small if statements gazelle@shell.xmission.com (Kenny McCormack) - 2020-03-30 13:04 +0000
Re: Coding style for small if statements Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2020-03-30 06:17 -0700
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-04-04 14:09 -0700
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-18 02:09 -0800
Re: Coding style for small if statements Jens Stuckelberger <Jens_Stuckelberger@nowhere.net> - 2020-02-10 01:47 +0000
Re: Coding style for small if statements Bonita Montero <Bonita.Montero@gmail.com> - 2020-02-12 17:54 +0100
Re: Coding style for small if statements Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-02-20 07:18 -0800
Re: Coding style for small if statements fir <profesor.fir@gmail.com> - 2020-02-29 03:30 -0800
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