author | wenzelm |
Mon, 05 Sep 2016 22:09:52 +0200 | |
changeset 63805 | c272680df665 |
parent 56744 | 0b74d1df4b8e |
child 64370 | 865b39487b5d |
permissions | -rw-r--r-- |
/* Title: Pure/PIDE/document_id.scala Module: PIDE Author: Makarius Unique identifiers for document structure. NB: ML ticks forwards > 0, JVM ticks backwards < 0. */ package isabelle object Document_ID { type Generic = Long type Version = Generic type Command = Generic type Exec = Generic val none: Generic = 0 val make = Counter.make() def apply(id: Generic): String = Value.Long.apply(id) def unapply(s: String): Option[Generic] = Value.Long.unapply(s) }