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From: cross@spitfire.i.gajendra.net (Dan Cross)
Newsgroups: comp.lang.c
Subject: Re: Taming The Switch-Statement
Date: Wed, 14 Oct 2026 19:47:22 -0000 (UTC)
Organization: PANIX Public Access Internet and UNIX, NYC
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Originator: cross@spitfire.i.gajendra.net (Dan Cross)
Xref: csiph.com comp.lang.c:403163

In article <11aoff0$1n82v$1@dont-email.me>, bart  <bc@freeuk.com> wrote:
>On 14/10/2026 13:38, Dan Cross wrote:
>> In article <11anobe$1dt0e$1@dont-email.me>, bart  <bc@freeuk.com> wrote:
>
>> Yes, I am aware that you will tell me that it is justified
>> because that problem is actually the one worth solving, and the
>> others are not; you needn't bother.  Simply put, I disagree that
>> that one problem is sufficiently important to warrant its own
>> solution, particularly when something more general is already
>> known and available in the language (labeled break/continue).
>
>I missed this bit.
>
>Is labeled break now available in C?

It's in C2y, and has been implemented in (at least) LLVM/clang
and GCC.  I don't know about other compilers.

>If so, how would it be used here:
>
>
>    while (1) {
>        switch (x) {
>        case y:
>            Break;
>
>where that Break is meant to quit the loop.

term% cat lb.c
#include <stdio.h>

int
main(void)
{
        int sum = 0;

        outer:
        for (int i = 0; i < 100; i++) {
                for (int j = 0; j < 100; j++) {
                        int p = i * j;
                        switch (p) {
                        case 500:
                                break outer;
                        default:
                                sum += p;
                                break;
                        }
                }
        }
        printf("sum = %d\n", sum);

        return 0;
}
term% clang-23 -std=c2y -o lb lb.c
term% ./lb
sum = 235000
term% gcc-16 -std=c2y -o lb lb.c
term% ./lb
sum = 235000
term% sed 's/outer./\;/' lb.c >lb2.c
term% clang-23 -std=c2y -o lb2 lb2.c
term% ./lb2
sum = 24500500
term% 

>Remember that if DMR hadn't made that screw-up in 1972 it would simply 
>have been as it is above with his choice of keyword in place of Break.

As I said in my other post, you incorrectly assume that that was
the fundamental issue, when really it's just a detail: the
problem was that no facility to break out of nested control
structures as provided.  Remedied now!

>But I would be interested in trying out the new feature.

So do it.  You don't need me to hold your hand.

	- Dan C.