src/Pure/System/message_channel.ML

--- a/src/Pure/System/message_channel.ML	Mon Sep 04 21:03:13 2023 +0200
+++ b/src/Pure/System/message_channel.ML	Wed Sep 06 14:09:27 2023 +0200
@@ -17,7 +17,7 @@
 
 datatype message = Shutdown | Message of XML.body list;
 
-datatype T = Message_Channel of {mbox: message Mailbox.T, thread: Thread.thread};
+datatype T = Message_Channel of {mbox: message Mailbox.T, thread: Isabelle_Thread.T};
 
 fun shutdown (Message_Channel {mbox, thread}) =
  (Mailbox.send mbox Shutdown;