--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/Tools/Demo/etc/options Sat Nov 25 16:13:08 2023 +0100
@@ -0,0 +1,6 @@
+(* :mode=isabelle-options: *)
+
+section "Demo"
+
+option demo_prefix : string = ""
+ -- "line prefix for output of arguments"