Prolog Clear List of negative elements without using cuts

Question

How do I write a procedure in Prolog that clears a list of integers of its negative elements and returns the result in a new list? Without using cuts but can use negation.

Answer 1

In SWI-Prolog you can use exclude/3

?- exclude(negative, [-1, -0.5, 0, 0.5, 1], L).
L = [0, 0.5, 1].

provided that you have a definition for negative/1:

negative(Number) :-
    Number < 0.