(* Title: Pure/Concurrent/thread_position.ML
Author: Makarius
Thread-local position information.
*)
signature THREAD_POSITION =
sig
type T = {line: int, offset: int, end_offset: int, props: (string * string) list}
val none: T
val get: unit -> T
val setmp: T -> ('a -> 'b) -> 'a -> 'b
end;
structure Thread_Position: THREAD_POSITION =
struct
type T = {line: int, offset: int, end_offset: int, props: (string * string) list};
val var = Thread_Data.var () : T Thread_Data.var;
val none: T = {line = 0, offset = 0, end_offset = 0, props = []};
fun get () = (case Thread_Data.get var of NONE => none | SOME pos => pos);
fun setmp pos f x = Thread_Data.setmp var (if pos = none then NONE else SOME pos) f x;
end;