changeset 52530 | 99dd8b4ef3fe |
child 52531 | 21f8e0e151f5 |
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/Pure/PIDE/document_id.scala Fri Jul 05 15:38:03 2013 +0200 @@ -0,0 +1,24 @@ +/* Title: Pure/PIDE/document_id.scala + Author: Makarius + +Unique identifiers for document structure. + +NB: ML ticks forwards > 0, JVM ticks backwards < 0. +*/ + +package isabelle + + +object Document_ID +{ + type ID = Long + val ID = Properties.Value.Long + + type Version = ID + type Command = ID + type Exec = ID + + val none: ID = 0 + val make = Counter() +} +