sharedobjgen/src/Type.m3


 Copyright (C) 1989, Digital Equipment Corporation           
 All rights reserved.                                        
 See the file COPYRIGHT for a full description.              

File: Type.m3 Last Modified On Mon Feb 28 16:52:17 PST 1994 by wobber Modified On Fri Jun 11 16:48:09 PDT 1993 by owicki Modified On Mon May 17 14:03:42 PDT 1993 by mjordan Modified On Fri Feb 2 10:35:09 PST 1990 by gnelson Modified On Wed Dec 20 18:07:50 1989 by kalsow

MODULE Type;

IMPORT Atom, Fmt, SOxCodeUtils, Text, Value, ValueProc;

<* FATAL SOxCodeUtils.Error *>

TYPE
  Foo = OBJECT
          name    : Qid;
          visited         := FALSE;
          brandsOK        := TRUE;
        END;

REVEAL T = Foo BRANDED OBJECT END;

PROCEDURE ToText (t: T; byName: BOOLEAN := TRUE): Text.T =
  VAR text: Text.T;
  BEGIN
    IF t = NIL THEN RETURN "" END;
    IF t.name # NIL AND byName THEN RETURN QidToText(t.name); END;
    TYPECASE t OF
    | Char => RETURN "CHAR"
    | UserDefined (ud) =>
        IF NUMBER(ud.elts^) = 0 THEN
          text := "";
        ELSE
          text := Atom.ToText(ud.elts[0]);
          FOR i := 1 TO LAST(ud.elts^) DO
            text := text & ", " & Atom.ToText(ud.elts[i]);
          END;
        END;
        RETURN "{" & text & "}";
    | Enumeration (enum) =>
        IF enum = boolean THEN RETURN "BOOLEAN"; END;
        RAISE SOxCodeUtils.Error("Run time error -- shouldn't occur");
    | Subrange (sub) =>
        VAR
          min, max: INTEGER;
          ud      : UserDefined;
        BEGIN
          IF sub = integer THEN RETURN "INTEGER" END;
          IF sub = longint THEN RETURN "LONGINT" END;
          IF sub.base = longint THEN
            WITH min = NARROW(sub.min, Value.Longint).val,
                 max = NARROW(sub.max, Value.Longint).val DO
              RETURN "[" & Fmt.LongInt(min) & "L.." & Fmt.LongInt(max) & "L]";
            END;
          END;
          min := NARROW(sub.min, Value.Integer).val;
          max := NARROW(sub.max, Value.Integer).val;
          IF sub.base = integer THEN
            RETURN "[" & Fmt.Int(min) & ".." & Fmt.Int(max) & "]"
          END;
          IF sub.base = char THEN
            RETURN "[VAL(" & Fmt.Int(min) & ", CHAR) .. VAL("
                     & Fmt.Int(max) & ", CHAR)]"
          END;
          ud := NARROW(sub.base, UserDefined);
          RETURN
            "[" & ToText(sub.base) & "." & Atom.ToText(ud.elts[min]) & ".."
              & ToText(sub.base) & "." & Atom.ToText(ud.elts[max]) & "]";
        END;
    | Real => RETURN "REAL";
    | LongReal => RETURN "LONGREAL";
    | Extended => RETURN "EXTENDED";
    | Reference (ref) =>
        TYPECASE ref OF
        | Opaque (o) =>
            (* Type can only be displayed by name *)
            RETURN "***Error*** Opaque type only printed by name: "
                     & "supertype " & ToText(o.revealedSuperType);

RETURN Atom.ToText(t.name.intf) & . & Atom.ToText(t.name.item)

        | Object, Ref =>
            IF ref.brand # NIL THEN
              text := "BRANDED \"" & Atom.ToText(ref.brand) & "\" ";
            ELSE
              text := ""
            END;
            TYPECASE ref OF
            | Object (o) =>
                RETURN ToText(o.super) & " " & text & "OBJECT\n"
                         & FieldsToText(o.fields) & "\nMETHODS\n"
                         & MethodsToText(o.methods) & "\nEND";
            | Ref (r) =>
                IF NOT r.traced THEN text := "UNTRACED " & text END;
                RETURN text & "REF " & ToText(r.target, TRUE);
            ELSE
              RAISE SOxCodeUtils.Error("Run time error -- shouldn't occur");
            END;
        ELSE
          RAISE SOxCodeUtils.Error("Run time error -- shouldn't occur");
        END;
    | Array (arr) =>
        IF arr.index = NIL THEN
          text := "";
        ELSE
          text := ToText(arr.index);
        END;
        RETURN "ARRAY " & text & " OF " & ToText(arr.element);
    | Packed (p) =>
        RETURN "BITS " & Fmt.Int(p.size) & "FORF " & ToText(p.base);
    | Record (rec) => RETURN "RECORD " & FieldsToText(rec.fields) & " END";
    | Set (set) => RETURN "SET OF " & ToText(set.range);
    | Procedure (proc) => RETURN "PROCEDURE" & SigToText(proc.sig);
    ELSE
      RAISE SOxCodeUtils.Error("Run time error -- shouldn't occur");
    END;
  END ToText;

PROCEDURE QidToText (qid: Qid): TEXT =
  BEGIN
    IF qid.intf = nullAtm THEN
      RETURN Atom.ToText(qid.item)
    ELSE
      RETURN Atom.ToText(qid.intf) & "." & Atom.ToText(qid.item)
    END;
  END QidToText;

PROCEDURE SigToText (sig: Signature): TEXT =
  VAR
    result: TEXT;
    raises: TEXT;
  BEGIN
    IF sig.result # NIL THEN
      result := ": " & ToText(sig.result);
    ELSE
      result := "";
    END;
    IF sig.raises = NIL THEN
      raises := " RAISES ANY"
    ELSIF NUMBER(sig.raises^) = 0 THEN
      raises := "";
    ELSE
      raises := " RAISES {" & QidToText(sig.raises[0].qid);
      FOR i := 1 TO LAST(sig.raises^) DO
        raises := raises & ", " & QidToText(sig.raises[i].qid);
      END;
      raises := raises & "}";
    END;
    RETURN "(" & FormalsToText(sig.formals) & ")" & result & raises;
  END SigToText;

PROCEDURE FieldsToText (f: REF ARRAY OF Field): TEXT =
  VAR
    notFirst := FALSE;
    text     := "";
  BEGIN
    FOR i := 0 TO LAST(f^) DO
      IF notFirst THEN text := text & "; "; END;
      notFirst := TRUE;
      text := text & Atom.ToText(f[i].name) & ": " & ToText(f[i].type);
      IF f[i].default # NIL THEN
        text := text & ":= " & ValueProc.ToText(f[i].default, f[i].type);
      END;
    END;
    RETURN text;
  END FieldsToText;

PROCEDURE MethodsToText (m: REF ARRAY OF Method): TEXT =
  VAR
    notFirst := FALSE;
    text     := "";
  BEGIN
    FOR i := 0 TO LAST(m^) DO
      IF notFirst THEN text := text & ";\n"; END;
      notFirst := TRUE;
      text := text & Atom.ToText(m[i].name) & SigToText(m[i].sig);
      IF m[i].default # NIL THEN
        text := text & ":= ";
        TYPECASE m[i].default OF
          MethodDefault1 (md1) => text := text & QidToText(md1.qid);
        | MethodDefault2 (md2) =>
            text :=
              text & ToText(md2.obType) & "." & Atom.ToText(md2.method);
        ELSE
          RAISE SOxCodeUtils.Error("Run time error -- shouldn't occur");
        END;
      END;
    END;
    RETURN text;
  END MethodsToText;

PROCEDURE FormalsToText (f: REF ARRAY OF Formal): TEXT =
  VAR
    notFirst       := FALSE;
    text           := "";
    modeName       := ARRAY Mode OF TEXT{"", "VAR ", "READONLY "};
    outPrag : TEXT;
  BEGIN
    FOR i := 0 TO LAST(f^) DO
      IF notFirst THEN text := text & "; "; END;
      notFirst := TRUE;
      IF f[i].outOnly THEN outPrag := "<*OUT*> " ELSE outPrag := "" END;
      text := text & modeName[f[i].mode] & " " & outPrag
                & Atom.ToText(f[i].name) & ": " & ToText(f[i].type);
      IF f[i].default # NIL THEN
        text := text & ":= " & ValueProc.ToText(f[i].default, f[i].type);
      END;
    END;
    RETURN text;
  END FormalsToText;

PROCEDURE MayBeRefAny (t: T): BOOLEAN =
  BEGIN
    IF t = refany THEN RETURN TRUE; END;
    TYPECASE t OF
    | Ref, Object => RETURN FALSE;
    | Opaque (o) => RETURN MayBeRefAny(o.revealedSuperType);
    ELSE
      RETURN FALSE               (* e.g.  type TEXT *)
    END;
  END MayBeRefAny;

PROCEDURE NamedType (t: T): BOOLEAN =
  BEGIN
    RETURN t.name # NIL;
  END NamedType;

PROCEDURE Size (t: T): INTEGER = BEGIN END Size;

PROCEDURE MinSize (t: T): INTEGER = BEGIN END MinSize;

PROCEDURE Alignment (t: T): INTEGER = BEGIN END Alignment;

PROCEDURE Bounds (t: T): Interval.T = BEGIN END Bounds;

PROCEDURE Base (t: T): T = BEGIN END Base;

PROCEDURE IsTraced (t: T): BOOLEAN = BEGIN END IsTraced;

PROCEDURE IsEmpty (t: T): BOOLEAN = BEGIN END IsEmpty;

VAR nullAtm: Atom.T;

BEGIN
  nullAtm := Atom.FromText("");
  integer := NEW(Subrange, name := NEW(Qid, intf := nullAtm,
                                       item := Atom.FromText("INTEGER")),
                 min := NEW(Value.Integer, val := FIRST(INTEGER)),
                 max := NEW(Value.Integer, val := LAST(INTEGER)));
  integer.base := integer;
  longint := NEW(Subrange, name := NEW(Qid, intf := nullAtm,
                                       item := Atom.FromText("LONGINT")),
                 min := NEW(Value.Longint, val := FIRST(LONGINT)),
                 max := NEW(Value.Longint, val := LAST(LONGINT)));
  longint.base := longint;

  cardinal := NEW(Subrange, name := NEW(Qid, intf := nullAtm,
                                        item := Atom.FromText("CARDINAL")),
                  base := integer, min := NEW(Value.Integer, val := 0),
                  max := integer.max);
  longcard := NEW(Subrange, name := NEW(Qid, intf := nullAtm,
                                        item := Atom.FromText("LONGCARD")),
                  base := longint, min := NEW(Value.Longint, val := 0L),
                  max := longint.max);

  boolean := NEW(
               UserDefined, name := NEW(Qid, intf := nullAtm,
                                        item := Atom.FromText("BOOLEAN")));
  boolean.elts := NEW(REF ARRAY OF Atom.T, 2);
  boolean.elts[0] := Atom.FromText("FALSE");
  boolean.elts[1] := Atom.FromText("TRUE");

  char := NEW(Char, name := NEW(Qid, intf := nullAtm,
                                item := Atom.FromText("CHAR")));
  real := NEW(Real, name := NEW(Qid, intf := nullAtm,
                                item := Atom.FromText("REAL")));
  longreal :=
    NEW(LongReal, name := NEW(Qid, intf := nullAtm,
                              item := Atom.FromText("LONGREAL")));
  extended :=
    NEW(Extended, name := NEW(Qid, intf := nullAtm,
                              item := Atom.FromText("EXTENDED")));
  refany := NEW(Reference, name := NEW(Qid, intf := nullAtm,
                                       item := Atom.FromText("REFANY")),
                traced := TRUE);
  address := NEW(Reference, name := NEW(Qid, intf := nullAtm,
                                        item := Atom.FromText("ADDRESS")),
                 traced := FALSE);
  root := NEW(Object, name := NEW(Qid, intf := nullAtm,
                                  item := Atom.FromText("ROOT")),
              traced := TRUE, fields := NEW(REF ARRAY OF Field, 0),
              methods := NEW(REF ARRAY OF Method, 0));
  untracedRoot :=
    NEW(Object, name := NEW(Qid, intf := nullAtm,
                            item := Atom.FromText("UNTRACED ROOT")),
        traced := FALSE, fields := NEW(REF ARRAY OF Field, 0),
        methods := NEW(REF ARRAY OF Method, 0));
  null := NEW(Reference, name := NEW(Qid, intf := nullAtm,
                                     item := Atom.FromText("NULL")));
  text := NEW(Opaque, name := NEW(Qid, intf := nullAtm,
                                  item := Atom.FromText("TEXT")),
              revealedSuperType := refany);
  mutex := NEW(Opaque, name := NEW(Qid, intf := nullAtm,
                                   item := Atom.FromText("MUTEX")),
               revealedSuperType := root);
END Type.

interface Type is in:


interface Value is in:


interface ValueProc is in: