1.1 --- a/src/Pure/PIDE/document.scala	Sun Feb 26 18:19:44 2012 +0100
     1.2 +++ b/src/Pure/PIDE/document.scala	Sun Feb 26 18:25:28 2012 +0100
     1.3 @@ -307,7 +307,7 @@
     1.4        State().define_version(Version.init, Assignment.init).assign(Version.init.id)._2
     1.5    }
     1.6  
     1.7 -  sealed case class State(
     1.8 +  sealed case class State private(
     1.9      val versions: Map[Version_ID, Version] = Map.empty,
    1.10      val commands: Map[Command_ID, Command.State] = Map.empty,  // static markup from define_command
    1.11      val execs: Map[Exec_ID, Command.State] = Map.empty,  // dynamic markup from execution