src/HOL/Import/import.ML
changeset 32740 9dd0a2f83429
parent 32091 30e2ffbba718
child 32970 fbd2bb2489a8
     1.1 --- a/src/HOL/Import/import.ML	Tue Sep 29 14:59:24 2009 +0200
     1.2 +++ b/src/HOL/Import/import.ML	Tue Sep 29 16:24:36 2009 +0200
     1.3 @@ -4,7 +4,7 @@
     1.4  
     1.5  signature IMPORT =
     1.6  sig
     1.7 -    val debug      : bool ref
     1.8 +    val debug      : bool Unsynchronized.ref
     1.9      val import_tac : Proof.context -> string * string -> tactic
    1.10      val setup      : theory -> theory
    1.11  end
    1.12 @@ -21,7 +21,7 @@
    1.13  structure Import :> IMPORT =
    1.14  struct
    1.15  
    1.16 -val debug = ref false
    1.17 +val debug = Unsynchronized.ref false
    1.18  fun message s = if !debug then writeln s else ()
    1.19  
    1.20  fun import_tac ctxt (thyname, thmname) =