(* Title: Pure/ML-Systems/polyml-5.0.ML
ID: $Id$
Compatibility wrapper for Poly/ML 5.1.
*)
use "ML-Systems/polyml.ML";
val pointer_eq = PolyML.pointerEq;
(* improved versions of use_text/file *)
fun use_text name (print, err) verbose txt =
let
val in_buffer = ref (explode txt);
val out_buffer = ref ([]: string list);
fun output () = implode (rev (case ! out_buffer of "\n" :: cs => cs | cs => cs));
val line_no = ref 1;
fun line () = ! line_no;
fun get () =
(case ! in_buffer of
[] => ""
| c :: cs => (in_buffer := cs; if c = "\n" then line_no := ! line_no + 1 else (); c));
fun put s = out_buffer := s :: ! out_buffer;
fun exec () =
(case ! in_buffer of
[] => ()
| _ => (PolyML.compilerEx (get, put, line, name) (); exec ()));
in
exec () handle exn => (err (output ()); raise exn);
if verbose then print (output ()) else ()
end;
fun use_file output verbose name =
let
val instream = TextIO.openIn name;
val txt = TextIO.inputAll instream before TextIO.closeIn instream;
in use_text name output verbose txt end;
(** multithreading **)
open Thread;
local
datatype 'a result =
Result of 'a |
Exn of exn;
fun capture f x = Result (f x) handle e => Exn e;
fun release (Result y) = y
| release (Exn e) = raise e;
fun message s =
(TextIO.output (TextIO.stdErr, (">>> " ^ s ^ "\n")); TextIO.flushOut TextIO.stdErr);
val critical_lock = Mutex.mutex ();
val critical_thread = ref (NONE: Thread.thread option);
in
(* critical section -- may be nested within the same thread *)
fun self_critical () =
(case ! critical_thread of
NONE => false
| SOME id => Thread.equal (id, Thread.self ()));
fun CRITICAL e =
if self_critical () then e ()
else
let
val _ =
if Mutex.trylock critical_lock then ()
else
(message "Waiting for critical lock";
Mutex.lock critical_lock;
message "Obtained critical lock");
val _ = critical_thread := SOME (Thread.self ());
val res = capture e ();
val _ = critical_thread := NONE;
val _ = Mutex.unlock critical_lock;
in release res end;
end;