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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c++
Subject: Re: two's complement idea
Date: Mon, 27 Jan 2020 02:20:54 -0800
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Xref: csiph.com comp.lang.c++:71621

Paavo Helde <myfirstname@osa.pri.ee> writes:

> On 25.01.2020 16:58, Bart wrote:
>
>> How would C++ help here, to avoid either that extra logic, or the use of
>> that goto?  Here's the current outline (for_each_pwq is a macro expanding
>> to a regular for-header):
>>
>>     L:
>>        A;
>>        for (...) {
>>           B;
>>           if (C) continue;
>>           D;
>>           goto L;
>>        }
>
> This is an example of some pretty convoluted logic, not even because
> of 'goto', but rather because of multiple code execution paths (two
> non-default exit paths from inner loop body and no normal exit
> path).  I would rewrite this along the lines:
>
> bool foobar(...) {
>     for (...) {
>         B;
>         if (!C) {
>              D;
>              return false;
>         }
>     }
>     return true;
> }
>
> while (true) {
>     A;
>     if (foobar(...)) {
>         break;
>     }
> }

To me this alternative is worse than the original.  Just a
personal reaction.  To give the peanut gallery something to hoot
about, and fya, the code (in C++!) may be recast as follows:

    void
    funky(){
        A;
        for (...) {
           B;
           if (C) continue;
           D;
           return  funky();
        }
    }

(Let me say in advance I will disregard any sort of heated
discussion about the inadvisability of the self-recursion
here.  I know a lot of people don't like it.  Get over it.)