From 0fa8feb4753338aba895a17b76f2fddee8ef6493 Mon Sep 17 00:00:00 2001
From: Markus Triska <triska@metalevel.at>
Date: Sat, 11 Jul 2020 19:52:01 +0200
Subject: [PATCH] use newly available character type in must_be/2

---
 src/lib/files.pl | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/src/lib/files.pl b/src/lib/files.pl
index 3d219173..b53b9bbb 100644
--- a/src/lib/files.pl
+++ b/src/lib/files.pl
@@ -57,13 +57,7 @@
 
 list_of_chars(Cs) :-
         must_be(list, Cs),
-        (   ground(Cs) ->
-            (   member(C, Cs), \+ atom_length(C, 1) ->
-                type_error(char, C, files_and_directories)
-            ;   true
-            )
-        ;   instantiation_error(s)
-        ).
+        maplist(must_be(character), Cs).
 
 directory_files(Directory, Files) :-
         list_of_chars(Directory),
-- 
2.54.0