not()

Hi!

Since I am new to prolog I am not fully sure, that that is realy a bug.

The Problem:
I created a file test.pro:

---test.pro---
female(anita).
male(X) :- not(female(X)).
--------------

And did run gprolog:

---gprolog----
GNU Prolog 1.2.18
By Daniel Diaz
Copyright (C) 1999-2004 Daniel Diaz
| ?- consult('test.pro').
compiling /home/cip/nf/spguleis/tmp/test.pro for byte code...
/home/cip/nf/spguleis/tmp/test.pro compiled, 2 lines read - 484 bytes
written, 9 ms

yes
| ?- female(anita).

(1 ms) yes
| ?- male(guido).
uncaught exception: error(existence_error(procedure,not/1),male/1)
| ?-
---------------

I did try on 64 and 32 bit-Versions. Allways the latest packages for
Fedora 6 and Debian 4.
I did also download the latest source
(http://www.gprolog.org/gprolog-1.3.0.tar.gz) and compiled it on
Fedora/X64
(On fedora/X64 (self compiled gprolog version) comes
system_error(cannot_catch_throw(error(existence_error(procedure,not/1),male/1)))


On our computer at university we have also swi-prolog. The same query
works fine there.


Please don't dress me down if that is not a bug ;)


Guido
Germany