Constraining two vectors to be different

[Thomas Bourdeaud'huy]

Hi, I'm using the FD solver,
and  try to define the predicate allDiferent(List_Of_Vectors)
I use this predicate not to verify that all the vectors are different,
but to constrain the variables of these vectors not to allow them to be
equals...

I know that \= and #\=# exist, but i defined :

vectDif(E1,E2):-
        \=(E1,E2).

notIn(_,[]):-!.
notIn(E,[E1|List]):-
        vectDif(E,E1),
        notIn(E,List).

tousDif([_]):-!.
tousDif([E|List]):-
        notIn(E,List),
        tousDif(List).

And tested : 

tousDif([[1,2],[3,4]]).
yes

tousDif([[1,2],[X,4]]).
yes

tousDif([[1,2],[X,2]]).
no

The last result is not the one i needed : i just wanted to make X <>
1...

If I use  #\= or #\=# in the definition of vectDif, the results are : 

tousDif([[1,2],[3,4]]).      
uncaught exception: error(type_error(fd_evaluable,[1,2]),(#\=)/2)

tousDif([[1,2],[X,4]]).      
uncaught exception: error(type_error(fd_evaluable,[1,2]),(#\=)/2)

What's wrong with my implementation ? Is there a 'dif' function in GNU
Prolog ? 

Thanks, 

Thomas Bourdeaud'huy
Ecole Centrale de Lille