From: Mark Thom <markjordanthom@gmail.com>
Date: Thu, 28 Mar 2019 03:13:36 +0000 (-0600)
Subject: make current_predicate/1 more general, re: #66
X-Git-Tag: v0.8.110~149
X-Git-Url: https://git.sagredo.dev/?a=commitdiff_plain;h=e7bc01369a5d59856d31f96d5f35f743d2e9c8c0;p=scryer-prolog.git

make current_predicate/1 more general, re: #66
---

diff --git a/src/prolog/lib/builtins.pl b/src/prolog/lib/builtins.pl
index 52fd1a7a..ff7a6a71 100644
--- a/src/prolog/lib/builtins.pl
+++ b/src/prolog/lib/builtins.pl
@@ -730,12 +730,10 @@ match_builtins(call, N) :-
     match_builtins(Name, Arity).
 
 current_predicate(Pred) :-
-    (  var(Pred) -> throw(error(type_error(predicate_indicator, Pred), current_predicate/1))
-    ;  Pred = _ / _ ->
-       (  '$get_current_predicate_list'(Ls),
-	  '$iterate_predicate_list'(Ls, Pred)
-       )
-    ;  throw(error(type_error(predicate_indicator, Pred), current_predicate/1))
+    (  nonvar(Pred), Pred \= _ / _
+    -> throw(error(type_error(predicate_indicator,Pred), current_predicate/1))
+    ;  '$get_current_predicate_list'(Ls),
+       '$iterate_predicate_list'(Ls, Pred)
     ).
 
 bb_put(Key, Value) :- atom(Key), !, '$store_global_var'(Key, Value).