Re: Lists in Learn Prolog Now

wooks wrote:

a2b([a|A], [b|B]) :-
       a2b([], []).
a2b([a|A], [b|B]) :-
       a2b(A, B).
[...]
I have a much better than average understanding of recursion 

then you should understand that having only recursive clauses, queries
to this predicate can only fail or loop infinitely; that holds in
logic just as in a functional language.

Cheers

Bart Demoen
.