X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fcomponents%2Fgrafite_engine%2FgrafiteSync.mli;h=bac7eee9b874e130d7ca123e9626ce2cd9fb2cf3;hb=064980eacc2efe70ffee96134d75dfa37506fc36;hp=d15896dab89823a41c8f9d6ab2fad4d522fdb0e1;hpb=42f25c258b0b199ee96dd8eaa3d44c86eb6916ab;p=helm.git

diff --git a/helm/software/components/grafite_engine/grafiteSync.mli b/helm/software/components/grafite_engine/grafiteSync.mli
index d15896dab..bac7eee9b 100644
--- a/helm/software/components/grafite_engine/grafiteSync.mli
+++ b/helm/software/components/grafite_engine/grafiteSync.mli
@@ -39,7 +39,7 @@ val prefer_coercion:
   GrafiteTypes.status -> UriManager.uri -> GrafiteTypes.status 
 
 val time_travel: 
-  present:GrafiteTypes.status -> past:GrafiteTypes.status -> unit
+  present:GrafiteTypes.status -> ?past:GrafiteTypes.status -> unit -> unit
 
   (* also resets the imperative part of the status 
    * init: the baseuri of the current script *)