src/Pure/System/command_line.ML

some rephrasing to ensure that this becomes cheap "foreach" and not expensive "map" (cf. 0fc032898b05);

(*  Title:      Pure/System/command_line.ML
    Author:     Makarius

Support for Isabelle/ML command line tools.
*)

signature COMMAND_LINE =
sig
  val tool: (unit -> int) -> unit
  val tool0: (unit -> unit) -> unit
end;

structure Command_Line: COMMAND_LINE =
struct

fun tool body =
  uninterruptible (fn restore_attributes => fn () =>
    let val rc =
      restore_attributes body () handle exn =>
        let
          val _ =
            Runtime.exn_error_message exn
              handle _ => Output.error_message "Exception raised, but failed to print details!";
        in if Exn.is_interrupt exn then 130 else 1 end;
    in if rc = 0 then () else exit rc end) ();

fun tool0 body = tool (fn () => (body (); 0));

end;