(*  Title:      Pure/ML-Systems/mosml.ML

    ID:         $Id$

    Author:     Lawrence C Paulson, Cambridge University Computer Laboratory

    Copyright   1999  University of Cambridge

Compatibility file for Moscow ML 2.01

NOTE: saving images does not work; may run it interactively as follows:

$ cd Isabelle/src/Pure

$ isabelle RAW_ML_SYSTEM

> val ml_system = "mosml";

> use "ML-Systems/mosml.ML";

> use "ROOT.ML";

> Session.finish ();

> cd "../FOL";

> use "ROOT.ML";

> Session.finish ();

> cd "../ZF";

> use "ROOT.ML";

*)

(** ML system related **)

val ml_system_fix_ints = false;

fun forget_structure _ = ();

load "Obj";

load "Bool";

load "Int";

load "Real";

load "ListPair";

load "OS";

load "Process";

load "FileSys";

load "IO";

exception Interrupt;

use "ML-Systems/exn.ML";

use "ML-Systems/universal.ML";

use "ML-Systems/multithreading.ML";

use "ML-Systems/time_limit.ML";

use "ML-Systems/ml_name_space.ML";

(*low-level pointer equality*)

local val cast : 'a -> int = Obj.magic

in fun pointer_eq (x:'a, y:'a) = (cast x = cast y) end;

(*proper implementation available?*)

structure IntInf =

struct

  fun divMod (x, y) = (x div y, x mod y);

  open Int;

end;

structure Substring =

struct

  open Substring;

  val full = all;

end;

structure Real =

struct

  open Real;

  val realFloor = real o floor;

end;

structure String =

struct

  fun isSuffix s1 s2 =

    let val n1 = size s1 and n2 = size s2

    in if n1 = n2 then s1 = s2 else n1 <= n2 andalso String.substring (s2, n2 - n1, n1) = s1 end;

  open String;

end;

structure Time =

struct

  open Time;

  fun toString t = Time.toString t

    handle Overflow => Real.toString (Time.toReal t);   (*workaround Y2004 bug*)

end;

structure OS =

struct

  open OS

  structure Process = Process

  structure FileSys = FileSys

end;

exception Option = Option.Option;

(*limit the printing depth*)

local

  val depth = ref 10;

in

  fun get_print_depth () = ! depth;

  fun print_depth n =

   (depth := n;

    Meta.printDepth := n div 2;

    Meta.printLength := n);

end;

(*interface for toplevel pretty printers, see also Pure/pure_setup.ML*)

(*the documentation refers to an installPP but I couldn't fine it!*)

fun make_pp path pprint = ();

fun install_pp _ = ();

(*dummy implementation*)

fun ml_prompts p1 p2 = ();

(*dummy implementation*)

fun profile (n: int) f x = f x;

(*dummy implementation*)

fun exception_trace f = f ();

(*dummy implementation*)

fun print x = x;

(** Compiler-independent timing functions **)

load "Timer";

fun start_timing () =

  let val CPUtimer = Timer.startCPUTimer();

      val time = Timer.checkCPUTimer(CPUtimer)

  in  (CPUtimer,time)  end;

fun end_timing (CPUtimer, {gc,sys,usr}) =

  let open Time  (*...for Time.toString, Time.+ and Time.- *)

      val {gc=gc2,sys=sys2,usr=usr2} = Timer.checkCPUTimer(CPUtimer)

  in  "User " ^ toString (usr2-usr) ^

      "  GC " ^ toString (gc2-gc) ^

      "  All "^ toString (sys2-sys + usr2-usr + gc2-gc) ^

      " secs"

      handle Time => ""

  end;

fun check_timer timer =

  let val {sys, usr, gc} = Timer.checkCPUTimer timer

  in (sys, usr, gc) end;

(* SML basis library fixes *)

structure TextIO =

struct

  fun canInput _ = raise IO.Io {cause = Fail "undefined", function = "canInput", name = ""};

  open TextIO;

  fun inputLine is =

    let val s = TextIO.inputLine is

    in if s = "" then NONE else SOME s end;

end;

(* ML command execution *)

(*Can one redirect 'use' directly to an instream?*)

fun use_text (tune: string -> string) _ _ _ _ _ txt =

  let

    val tmp_name = FileSys.tmpName ();

    val tmp_file = TextIO.openOut tmp_name;

  in

    TextIO.output (tmp_file, tune txt);

    TextIO.closeOut tmp_file;

    use tmp_name;

    FileSys.remove tmp_name

  end;

fun use_file _ _ _ _ _ name = use name;

(** interrupts **)      (*Note: may get into race conditions*)

(* FIXME proper implementation available? *)

fun interruptible f x = f x;

fun uninterruptible f x = f (fn (g: 'c -> 'd) => g) x;

(** OS related **)

(*dummy implementation*)

structure Posix =

struct

  structure ProcEnv =

  struct

    fun getpid () = 0;

  end;  

end;

local

fun read_file name =

  let val is = TextIO.openIn name

  in Exn.release (Exn.capture TextIO.inputAll is before TextIO.closeIn is) end;

fun write_file name txt =

  let val os = TextIO.openOut name

  in Exn.release (Exn.capture TextIO.output (os, txt) before TextIO.closeOut os) end;

in

fun system_out script =

  let

    val script_name = OS.FileSys.tmpName ();

    val _ = write_file script_name script;

    val output_name = OS.FileSys.tmpName ();

    val status =

      OS.Process.system ("perl -w \"$ISABELLE_HOME/lib/scripts/system.pl\" nogroup " ^

        script_name ^ " /dev/null " ^ output_name);

    val rc = if status = OS.Process.success then 0 else 1;

    val output = read_file output_name handle IO.Io _ => "";

    val _ = OS.FileSys.remove script_name handle OS.SysErr _ => ();

    val _ = OS.FileSys.remove output_name handle OS.SysErr _ => ();

  in (output, rc) end;

end;

val cd = OS.FileSys.chDir;

val pwd = OS.FileSys.getDir;

val string_of_pid = Int.toString;

fun getenv var =

  (case Process.getEnv var of

    NONE => ""

  | SOME txt => txt);