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Re: Why should `break' and `continue' in functions not break loops runni
Re: Why should `break' and `continue' in functions not break loops running outside of the function?
Sat, 30 Oct 2021 18:02:38 +0300
On Sat, Oct 30, 2021 at 4:50 PM Greg Wooledge <email@example.com> 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
> What are you actually trying to do?
Nothing. Idle curiosity.