(* Title: Pure/PIDE/document_id.ML
Author: Makarius
Unique identifiers for document structure.
NB: ML ticks forwards > 0, JVM ticks backwards < 0.
*)
signature DOCUMENT_ID =
sig
type generic = int
type version = generic
type command = generic
type exec = generic
type execution = generic
val none: generic
val make: unit -> generic
val parse: string -> generic
val print: generic -> string
end;
structure Document_ID: DOCUMENT_ID =
struct
type generic = int;
type version = generic;
type command = generic;
type exec = generic;
type execution = generic;
val none = 0;
val make = Counter.make ();
val parse = Value.parse_int;
val print = Value.print_int;
end;