Re: [Chicken-users] scheduling and coroutines

[Peter Bex]

On Sat, Feb 26, 2011 at 01:50:10PM +0100, Tomtom wrote:
> Now, how should I change the code in the routine ?
> 
> Buf if I change the routine by adding one argument to call/cc
> 
> (define (routine cont)
>   (let loop ((n 10))
>     (set! cont (call/cc cont n))
>     (if (> n 0)
>       (loop (- n 1)))))
> 
> Error: bad argument count - received 2 but expected 1: #<procedure
> (call-with-current-continuation proc1295)>
> 
> Well, I guess it's normal too, as call/cc is taking only one argument - so how
> am I supposed to pass this second argument ?

You don't pass it to call/cc. Call/cc merely *captures* the continuation
at that point and passes it to its lambda argument.  What you want is
to also pass the value to the continuation of the scheduler:

(define (routine cont)
  (let loop ((n 10))
    (display n)(newline)
    (set! cont (call/cc (lambda (k) (cont k n))))
    (if (> n 0)
    (loop (- n 1)))))

HTH,
Peter
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