print errors as goals (#1408)

2022-04-09 14:01:48 -06:00
parent 0876d46880
commit 00eab4d415
3 changed files with 27 additions and 19 deletions
--- a/src/loader.pl
+++ b/src/loader.pl
@@ -17,6 +17,14 @@
 :- use_module(library(pairs)).


+write_error(Error) :-
+    write('   '),
+    (  nonvar(Error),
+       functor(Error, error, 2) ->
+       writeq(Error)
+    ;  writeq(throw(Error))
+    ).
+
 '$print_message_and_fail'(Error) :-
    (  (  Error = error(existence_error(procedure, Expansion), Expansion)
       ;  Error = error(evaluation_error((_:_)/_),Expansion)
@@ -25,12 +33,10 @@
          ;  Expansion = term_expansion/2
          )  ->
          true
-       ;  write('caught: '),
-          writeq(Error),
+       ;  write_error(Error),
          nl
       )
-    ;  write('caught: '),
-       writeq(Error),
+    ;  write_error(Error),
       nl
    ),
    '$fail'.