diff --git a/src/lib/clpb.pl b/src/lib/clpb.pl
index 311d6115..b5deff81 100644
--- a/src/lib/clpb.pl
+++ b/src/lib/clpb.pl
@@ -1949,6 +1949,8 @@ Compatibility predicates.
 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
 
 
+:- meta_predicate(include(1, ?, ?)).
+
 include(_, [], []).
 include(Goal, [L|Ls0], Ls) :-
         (   call(Goal, L) ->
@@ -1957,6 +1959,8 @@ include(Goal, [L|Ls0], Ls) :-
         ),
         include(Goal, Ls0, Rest).
 
+:- meta_predicate(exclude(1, ?, ?)).
+
 exclude(_, [], []).
 exclude(Goal, [L|Ls0], Ls) :-
         (   call(Goal, L) ->