ProofEngineTypes.Fail printed correctly.

diff --git a/helm/matita/matitaExcPp.ml b/helm/matita/matitaExcPp.ml
index d6cddfaab85baeb16ae49a84a44abfed2fba1d90..a80d0a2fb8c5ffbbec9d751feda624686579d65b 100644 (file)
--- a/helm/matita/matitaExcPp.ml
+++ b/helm/matita/matitaExcPp.ml
@@ -49,6 +49,7 @@ let to_string =
         (".moo file '%s' has been compiled by a different version of matita, "
         ^^ "please recompile it")
         fname
+  | ProofEngineTypes.Fail msg -> "Tactic error: " ^ Lazy.force msg
   | Continuationals.Error s -> "Tactical error: " ^ Lazy.force s
   | exn -> "Uncaught exception: " ^ Printexc.to_string exn