[racket] Call-Site Code Replacement

Only this particular call site? Because in general, it would be simple to do:

#lang racket/base

(define (f a)
  (printf "(f ~a)\n" a)
  (set! the-f g)
  0)

(define the-f f)

(define (g a)
  (printf "(g ~a)\n" a)
  (set! the-f f)
  1)

(module+ main
  (for ([i (in-range 10)])
    (the-f i)))

OUTPUT:

(f 0)
(g 1)
(f 2)
(g 3)
(f 4)
(g 5)
(f 6)
(g 7)
(f 8)
(g 9)


On Mon, Oct 22, 2012 at 11:55 AM, Jan Burse <janburse at fastmail.fm> wrote:
> Dear All,
>
> I just wonder whether it is possible in a functional
> language to do call site replacement. I envision this
> as a special form of lazyness.
>
> Basically I would call somewhere a function f
> with an argument a:
>
>     ... (f a) ...
>
> The function would then manage to replace itself
> by a function g with an argument b:
>
>     ... (g b) ...
>
> So that the next time the original call site of (f a)
> is invoked in fact (g b) is invoked.
>
> Hints welcome.
>
> Bye
>
> ____________________
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>  http://lists.racket-lang.org/users



-- 
Jay McCarthy <jay at cs.byu.edu>
Assistant Professor / Brigham Young University
http://faculty.cs.byu.edu/~jay

"The glory of God is Intelligence" - D&C 93