Re: Why should `break' and `continue' in functions not break loops running outside of the function?

[Oğuz]

On Sat, Oct 30, 2021 at 4:50 PM Greg Wooledge <greg@wooledge.org> wrote:
> As Chet said, it's counterintuitive.  Most people don't expect function A
> to be able to affect loops inside function B.

I do, and a subshell can prevent function A from affecting loops
inside function B. But that is not a real problem, you wouldn't call,
say `break 3', when you're only 2 loop levels deep in a function
unless you wanted to exit from the loop from within the function is
called after returning.

> It's a violation of scope.

It's a violation of lexical scope, I'm asking why not implement
dynamic scope, what's wrong with it?

>
> Can you name *any* other language where functions can break out of their
> caller's loops?  The only thing that comes to mind for me is C's "longjmp",
> which I've never used even once.  (Not that I do any C programming these
> days, but back in the 1990s, I did.)

As far as I know `longjmp' is far more advanced than shell's
break/continue. I can't name another language, but netbsd sh, busybox
sh, and zsh are shells that implement dynamically scoped break and
continue.

>
> What are you actually trying to do?
>

Nothing. Idle curiosity.