proper support for "isabelle update -D DIR": avoid accidental exclusion of select_dirs (amending e5dafe9e120f);
(* Author: Lawrence C Paulson, Cambridge University Computer Laboratory
Copyright 1996 University of Cambridge
*)
section \<open>Blanqui's "guard" concept: protocol-independent secrecy\<close>
theory Auth_Guard_Shared
imports
Guard_OtwayRees
Guard_Yahalom
begin
end