dif/2: Omit entailed residual goals, if the arguments are not unifiable.

This addresses #135.
2020-08-22 17:49:02 +02:00
parent e75ebd9b6e
commit cc77ef680d
1 changed files with 3 additions and 1 deletions
--- a/src/lib/dif.pl
+++ b/src/lib/dif.pl
@@ -49,7 +49,9 @@ dif(X, Y) :-

 gather_dif_goals([]) --> [].
 gather_dif_goals([(X \== Y) | Goals]) -->
-    [dif(X, Y)],
+    (   { X \= Y } -> []
+    ;   [dif(X, Y)]
+    ),
    gather_dif_goals(Goals).

 attribute_goals(X) -->