Hi Cle, > The Prolog definitions are: > > member(X, [X|_]). > member(X, [_|T]) :- member(X, T). > > append(, L, L). > append([H|L1], L2, [H|L3]) :- append(L1, L2, L3).
You can directly translate them to Pilog, if you follow the rules: 1. Define clauses with 'be' in the style of 'de' 2. Variables start with '@' instead of an uppercase letter 3. Commas, :- and the final dot are omitted 4. Lists are surrounded by parentheses instead of brackets 5. Dotted pairs have a dot instead of '|' 6. The 'cut' operator is 'T' instead of '!' With that you get; (be member (@X (@X . @))) (be member (@X (@ . @Y)) (member @X @Y)) (be append (NIL @X @X)) (be append ((@A . @X) @Y (@A . @Z)) (append @X @Y @Z)) (in fact, I copy/pasted that from "lib/pilog.l:117" :-) > I already fail defining a correct Pilog member. This is, what I already got: > > (be mymember (@ NIL) T) > (be mymember (@X @L) (equal (-> @X) (car (-> @L)))) > (be mymember (@X @L) (mymember @X (cdr (-> @L)))) This is not so bad. The first clause is OK as it is. In the second clause you are doing it halfway correct. (-> @X) is the way to access a Pilog binding in a Lisp expression. You can use a Lisp expression in a clause if that expression has a variable in its CAR, then the CDR should be Lisp. The second clause could be (be mymember (@X @L) (@ = (-> @X) (car (-> @L)))) The third clause, however, is difficult to get straight in this way, as 'mymember' is not a Lisp function. So it is better to use the standard Prolog method of supplying a pattern like (@X . @) or (@ . @Y) to split a list, as in the Pilog clauses above. I really need to document Pilog! I have it on my todo list, but currently I try to document the database classes first. Cheers, - Alex -- UNSUBSCRIBE: mailto:picol...@software-lab.de?subject=unsubscribe