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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Do you insist on const-correctness?
Date: Sat, 30 Sep 2023 09:56:47 -0700
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Kaz Kylheku <864-117-4973@kylheku.com> writes:

[.. combining 'else' with 'for' or 'while', etc ..]


> [from some code written in 2011]
>
> static val lazy_flatten_scan(val list, val *escape)
> {
>   for (;;) {
>     if (list) {
>       val a = car(list);
>       if (nilp(a)) {
>         list = cdr(list);
>       } else if (atom(a)) {
>         return list;
>       } else do {
>         push(cdr(list), escape); /* safe mutation: *escape is a local var */
>         list = a;
>         a = car(list);
>       } while (consp(a));
>       return list;
>     } else if (*escape) {
>       list = pop(escape);
>     } else {
>       return nil;
>     }
>   }
> }
>
> I had no idea I've been doing it that long already, and that
> a "do" might have started it.  [...]

This code is truly horrific.

Ironically, combining 'do' directly with 'else' may be
responsible for a bug in the code.