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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: stopping a loop iteration without exiting it
Date: Sun, 07 Jan 2018 21:04:55 +0000
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Date: 2018-01-07T21:04:55+00:00
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Micah Waddoups <micahwelf@gmail.com> writes:

> On Wednesday, January 3, 2018 at 9:54:36 AM UTC-7, Mehdi Saada wrote:
>> Is there a way to tell to ignore the remaining of a loop ? Like an
>> exit statement, but instead of quiting the loop, it would go to the
>> next iteration.
>> Can we do this except with a recursive structure ?
>
> Of all the things I've read in this post, I think the closest thing to
> the ideals and standards of Ada is the `goto My_Loop` idea.  Making
> any named structure flow control accessible with the goto statement,
> only specifying the next loop of such, and exiting any inner loops in
> the process reduces code written in some cases and more importantly,
> it is very clear where the decision to exit/continue-next is made and
> exactly which loop is being jumped to the next iteration.  This
> short-circuit behavior is similar to the `and then` and `or else`
> convention used in Boolean condition testing.

It seems to me that some sensible naming conventions could do the job
quite well without changing the language.

   Foo : for J in 1 .. 10 loop
      if J = 5 or J = 6 then
         goto Continue_Foo;
      end if;
      K := K + J;
   <<Continue_Foo>>
   end loop Foo;

(I wanted to write <<Foo>> but no)

NB! I would never use a label in so small a context as this! Imagine
lots of checks and lots of code to skip.

Or perhaps <<Next_Foo>>, depending on how much one likes the C
'continue'.