1.1 --- a/src/HOL/Tools/Quickcheck/narrowing_generators.ML	Wed Jul 20 08:16:33 2011 +0200
     1.2 +++ b/src/HOL/Tools/Quickcheck/narrowing_generators.ML	Wed Jul 20 08:16:35 2011 +0200
     1.3 @@ -458,7 +458,9 @@
     1.4    else
     1.5      (if Config.get ctxt Quickcheck.quiet then () else Output.urgent_message
     1.6        ("Environment variable ISABELLE_GHC is not set. To use narrowing-based quickcheck, please set "
     1.7 -        ^ "this variable to your GHC Haskell compiler in your settings file."); [Quickcheck.empty_result])
     1.8 +        ^ "this variable to your GHC Haskell compiler in your settings file. "
     1.9 +        ^ "To deactivate narrowing-based quickcheck, set quickcheck_narrowing_active to false.");
    1.10 +      [Quickcheck.empty_result])
    1.11  
    1.12  (* setup *)
    1.13