Re: Back & Forth - Co-routines

On Sun, 9 Feb 2025 23:08:22 +0000, Anton Ertl wrote:

Paul Rubin <no.email@nospam.invalid> writes:

..

This is an attempt to make a counting function, like in Scheme:
>
(define (x)
 ((lambda (n)
   (lambda ()
     (set! n (+ 1 n))
     n)) 0))
>
(define a (x))
>
(a)  ; 1
(a)  ; 2, etc.

>
: x ( -- xt )
  here 0 , [{: addr :}d addr @ 1+ dup addr ! ;] ;
>
x alias a
x alias b
a . \ 1
a . \ 2
b . \ 1
a . \ 3
>

Hi,
But I can do it like this:
: ctr: create 0 , does> dup @ 1+ dup rot ! ;  ok
ctr: a
ctr: b
a . 1  ok
b . 1  ok
a . 2  ok
b . 2  ok
b . 3  ok
So, what is the difference between the two definitions?

- anton

Ahmed
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