[racket] [bug?] Racklog cut differs from Prolog cut

From: Erik Dominikus (erik.dominikus71 at gmail.com)
Date: Sun Aug 12 01:32:53 EDT 2012

Racket version:


Output of 'uname -a':

Linux kire 2.6.32-41-generic #91-Ubuntu SMP Wed Jun 13 11:43:55 UTC 2012
x86_64 GNU/Linux


In SWI Prolog (or any Prolog interpreter I think), querying a(X) gives
X=1 and X=2. Racklog only gives x=1.

How to reproduce:

Download 'a.pl' (attached).
Run 'prolog -f a.pl' (if using SWI Prolog).
Enter 'a(X).'.
Press ';' (semicolon) key until it prints false.

Download 'a.rkt' (attached).
Run 'racket a.rkt'.


Racklog gives x=1 and x=2.

Thank you.
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#lang racket

(require racklog)

(define %a
  (%rel (x)
        ((x) (%b x) !)
        ((x) (%c x))

(define %b
  (%rel ()
        ((1) !)

(define %c
  (%rel ()

(%find-all (x) (%a x))

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