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From: cross@spitfire.i.gajendra.net (Dan Cross)
Newsgroups: comp.lang.c
Subject: Re: Taming The Switch-Statement
Date: Thu, 15 Oct 2026 11:45:33 -0000 (UTC)
Organization: PANIX Public Access Internet and UNIX, NYC
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In article <11aqbqv$2avn3$1@dont-email.me>, bart  <bc@freeuk.com> wrote:
>On 15/10/2026 02:26, Dan Cross wrote:
>> In article <11aoqa9$1rgda$1@dont-email.me>, bart  <bc@freeuk.com> wrote:
>>> On 14/10/2026 20:30, Dan Cross wrote:
>>> [snip more of the same already hashed and rehashed ad naseum]
>>>
>>> As for multiple nested loops, this will fix that too, that's great. We
>>> just require some real examples of that being needed!
>> 
>> Here's a pretty terrible way to write part of a lexical
>> analyzer.  I just typed this in an hour or so ago.
>....
>
>Wow, it's impressive that you went to that trouble just to prove a point 
>about nested loops. (Even if it might have been a little bit contrived.)
>
>But this is an interesting pattern with all those breaks:
>
> [snip]
>
>It seems most uses of 'break;' to break out of a loop have disappeared 
>to be replaced with labeled versions.
>
>The remaining breaks are switch-breaks.
>
>Then I start looking at some of those "breaks;". Some (maybe one) is at 
>top-level, it jumps to the end of that switch, so the end of the while, 
>so is really 'continue'.
>
>Most are in nested switches, some of those jump to a 'break loop'. Some 
>jump somewhere else...
>
>Basically this is spaghetti code (I know you said it was terrible); your 
>eyes glaze over with breaks everywhere and you give up trying to figure 
>out the control flow.

Perhaps if I had spent more than like, 30 minutes, on it I would
have tidied it up.  The point was to illustrate a contrived
example where one might break out of nested switch statements,
loops inside of switch, switch inside of loops, loops inside of
switch inside of loops, and so on.

>There are examples like this:
>
>         continue;
>     default:
>         break;
>     }
>     break loop;
>
>Do you even need 'default: break;}' or even an empty default:?

You don't, but some compilers will complain if it isn't there.
See above.  It was merely a quick and dirty example.

>I then tried an experiment where I got rid of switch-break, to see what 
>C code with automatic switch-break would look like.
>
>It was a big improvement, now that you know that every case-blocks 
>proceeds to the end of that switch, and you don't need to double-check 
>every 'break' to see if it's to do with switches or loops:
>
>     break loop;
>     break loop;
>     break loop;
>     break loop;
>     break loop;
>     break loop;
>     break loop;
>     break loop;
>     break loop;
>     break loop;
>     break loop;
>     break loop;
>     break loop;
>     break sloop;
>     break loop;
>     break loop;
>     break loop;
>     break loop;
>     break;
>     break loop;
>     break;
>
>All these are known to be loops, even 'break;'.
>
>But also, labeled versions except three 'break loops' can be written as 
>'break', since 'switch break' does not exist. You're left with:
>
>     break loop;
>     break loop;
>     break loop;
>     break;
>     break;
>     break;
>     break;
>     break;
>     break;
>     break;
>     break;
>     break;
>     break;
>     break;
>     break;
>     break;
>     break;
>     break;
>     break;
>     break;
>     break;
>
>(Not ordered.) Compare with the first set.

Compare what?  Without the surrounding context, this is utterly
meaningless: this isn't a useful illustration of working code;
this is the output of `grep`.

(btw, if you `|sort |uniq -c` you can actually get counts!  You
can even `|sort |uniq -c |sort -n` to order by frequency of
occurrence!)

> >> [snip more of the same already hashed and rehashed ad naseum]
>
>Perhaps that reused keyword thing is a bigger deal than you think. The 
>effect of it is unnecessary obfuscation.

This is certainly not evidence of that.  This is just your
assertion that you took a silly example and apparently (maybe?)
improved it, based on some unstated, but apparently subjective,
criteria.

	- Dan C.