DEFINITION MODULE M3DL; (*NW 2.6.84 / 2.11.85*)
  FROM SYSTEM IMPORT ADDRESS;

  CONST WordSize = 16;
    nilval = 177777B;
    MaxCodeLength = 8;

  TYPE
    ObjPtr = POINTER TO Object;
    StrPtr = POINTER TO Structure;
    ParPtr = POINTER TO Parameter;
    PDPtr  = POINTER TO PDesc;
    KeyPtr = POINTER TO Key;

    ObjClass = (Header, Const, Typ, Var, Field, Proc, Code, Module, Temp);

    StrForm = (Undef, Bool, Char, Card, Int, Double, Real, String,
               Enum, Range, Pointer, Set, Array, Record, ProcTyp, Opaque);

    ConstValue =
      RECORD
        CASE : StrForm OF
          Bool:   B: BOOLEAN  |
          Char:   Ch: CHAR    |
          Int:    I: INTEGER  |
          Card, Enum: C: CARDINAL; prev: ObjPtr |
          Set:    S: BITSET   |
          Double: D: LONGINT  |
          Real:   R: REAL     |
          String: D0, D1, D2, D3: CARDINAL
        END
      END;

    Object =
      RECORD
        name: CARDINAL; (*index to name buffer*)
        typ: StrPtr;
        left, right, next: ObjPtr;
        exported: BOOLEAN;
        CASE class: ObjClass OF
          Header: kind: ObjClass; (*Proc, Module or Typ*)
                  last, heap: ObjPtr; withadr: INTEGER |
          Const:  conval: ConstValue |
          Typ:    mod: ObjPtr |
          Var:    param: BITSET;
                  vmod, vlev: CARDINAL; vadr: INTEGER |
          Field:  offset: INTEGER |
          Proc:   pd: PDPtr;
                  firstParam: ParPtr;
                  firstLocal: ObjPtr;
                  pmod: CARDINAL |
          Code:   cd: PDPtr;
                  firstArg: ParPtr;
                  cnum, length: CARDINAL |
          Module: key: KeyPtr;
                  firstObj, root: ObjPtr;
                  modno: CARDINAL |
          Temp:   baseref: CARDINAL
        END
      END;

    PDesc = RECORD
              CASE : BOOLEAN OF
                TRUE:   num, lev: CARDINAL; adr, size: INTEGER |
                FALSE:  cod: ARRAY [0..MaxCodeLength-1] OF CHAR
              END
            END;

    Structure =
      RECORD
        strobj: ObjPtr; (*object (type) naming structure*)
        size: INTEGER;
        ref: CARDINAL;
        CASE form: StrForm OF
          Undef, Bool, Char, Int, Card, Double, Real, String: |
          Enum:    ConstLink: ObjPtr; NofConst: CARDINAL |
          Range:   RBaseTyp: StrPtr;
                   min, max: INTEGER |
          Pointer: PBaseTyp: StrPtr;
                   BaseId: CARDINAL | (*to handle forward refs*)
          Set:     SBaseTyp: StrPtr |
          Array:   ElemTyp, IndexTyp: StrPtr;
                   dyn: BOOLEAN |
          Record:  firstFld: ObjPtr |
          ProcTyp: firstPar: ParPtr;
                   resTyp: StrPtr |
          Opaque:
        END
      END;

    Parameter  = RECORD name: CARDINAL; varpar: BOOLEAN;
                   typ: StrPtr; next: ParPtr
                 END;

    Key        = RECORD k0, k1, k2: CARDINAL
                 END;

  VAR mainmod, sysmod: ObjPtr;
    undftyp, booltyp, chartyp, inttyp, cardtyp, bitstyp, dbltyp, realtyp,
    proctyp, notyp, stringtyp, addrtyp, wordtyp: StrPtr;

  PROCEDURE ALLOCATE(VAR a: ADDRESS; n: CARDINAL);
  PROCEDURE Available(): CARDINAL;
  PROCEDURE ResetHeap(a: ADDRESS);
END M3DL.