FIXED: Possible non-determinism in write_html/2 on a mailbox that has…

… not been posted to.
SWI-Prolog · Feb 25, 2023 · e62c9a0 · e62c9a0
1 parent 17a093f
commit e62c9a0
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/html_write.pl b/html_write.pl
@@ -1249,7 +1249,8 @@
     write_html(T2, Out).
 write_html([mailbox(_, Box)|T], Out) :-
     !,
-    (   Box = accept(_, Accepted)
+    (   Box = accept(_, Accepted),
+        nonvar(Accepted)
     ->  write_html(Accepted, Out)
     ;   true
     ),