let command_error msg = raise (Command_error msg)
-class status = fun (b : string) ->
+class virtual status = fun (b : string) ->
let fake_obj =
NUri.uri_of_string "cic:/matita/dummy.decl",0,[],[],
NCic.Constant([],"",None,NCic.Implicit `Closed,(`Provided,`Theorem,`Regular))