Re: escaping from a recursive call

[Damien Mattei]

but in the general case  , i want a macro that can do it on any function
(i'm not sure it can be done because the continuation have to be captured
just before the call to the function and be inlined at the good place....)

On Wed, Nov 9, 2022 at 5:52 PM Olivier Dion <olivier.dion@polymtl.ca> wrote:

> On Wed, 09 Nov 2022, Damien Mattei <damien.mattei@gmail.com> wrote:
> > i need a way to escape not only the current call of a recursive function
> > (it is already done) but alls:
> >
> > example:
> >
> > (def (foo n)
> >      (cond ((= n 0) 'end0)
> >   ((= n 7) (return 'end7))
> >   (else (cons n (foo {n - 1})))))
>
> Is that what you want?
> --8<---------------cut here---------------start------------->8---
> (use-modules
>  (ice-9 control))
>
> (define (foo n)
>   (let/ec return
>     (let loop ((n n))
>       (cond
>        ((= n 0) 'end0)
>        ((= n 7) (return 'end7))
>        (else
>         (cons n (loop (1- n))))))))
>
> (pk (foo 5))
> (pk (foo 10))
> --8<---------------cut here---------------end--------------->8---
>
> --
> Olivier Dion
> oldiob.dev
>