diff --git a/src/list.c b/src/list.c
index e0c8c2e..fa9843a 100644
--- a/src/list.c
+++ b/src/list.c
@@ -1397,7 +1397,7 @@
 	return;  // empty list results in empty string
 
     if (argvars[1].v_type != VAR_UNKNOWN)
-	utf8 = (int)tv_get_number_chk(&argvars[1], NULL);
+	utf8 = (int)tv_get_bool_chk(&argvars[1], NULL);
 
     CHECK_LIST_MATERIALIZE(l);
     ga_init2(&ga, 1, 80);