Critical Mass Modula-3: obliqlibemb/src/ObEmbProxiedObj.m3

obliqlibemb/src/ObEmbProxiedObj.m3

Copyright (C) 1994, Digital Equipment Corporation Digital Internal Use Only All rights reserved. Last modified on Sun Aug 13 12:51:44 EDT 1995 by macintyre modified on Mon Sep 26 21:52:38 PDT 1994 by najork Created on Wed Jul 20 09:48:11 PDT 1994 by najork Used to be ObProxiedObj in Anim3D, but I don't want everything depending on Anim3D so I made a separate embedded language package

MODULE ObEmbProxiedObj;

IMPORT EmbProxiedObj, ObLoader, ObCommand, ObLib, ObValue, Obliq,
       SynLocation;

CONST
  pkgname = "EmbProxiedObj";

*************************************************************************** Wrapper for EmbProxiedObj.T ***************************************************************************

REVEAL
  T = Public BRANDED "ObEmbProxiedObj.T" OBJECT
  OVERRIDES
    Is := IsT;
  END;

PROCEDURE IsT (self: T; other: ObValue.ValAnything): BOOLEAN =
  BEGIN
    TYPECASE other OF
      T (oth) => RETURN self.po = oth.po;
    ELSE
      RETURN FALSE
    END;
  END IsT;

PROCEDURE GetArg (args    : ObValue.ArgArray;
                  idx     : INTEGER;
                  package : ObLib.T;
                  opCode  : ObLib.OpCode;
                  loc     : SynLocation.T) : EmbProxiedObj.T
    RAISES {ObValue.Error, ObValue.Exception} =
  BEGIN
    WITH raw = Obliq.ObjectSelect (args[idx], "raw") DO
      TYPECASE raw OF
      | T (node) =>
        RETURN node.po;
      ELSE
        ObValue.BadArgType (idx, pkgname, package.name, opCode.name, loc);
        RETURN NIL;      (* ... only to suppress compiler warning *)
      END;
    END;
  END GetArg;

*************************************************************************** Setup procedures ***************************************************************************

PROCEDURE SetupPackage () =
  PROCEDURE NewOpCode (name : TEXT; arity : INTEGER; code : Code) : OpCode =
    BEGIN
      RETURN NEW (OpCode, name := name, arity := arity, code := code);
    END NewOpCode;

  TYPE
    OpCodes = ARRAY OF ObLib.OpCode;
  VAR
    opCodes: REF OpCodes;
  BEGIN
    opCodes := NEW (REF OpCodes, NUMBER (Code));
    opCodes^ :=
        OpCodes {
            NewOpCode ("Error",   -1, Code.Error)
        };

    errorException := Obliq.NewException("EmbProxiedObj_Error");
    ObLib.Register (NEW (Package, name := pkgname, opCodes := opCodes));
    ObLib.RegisterHelp (pkgname, Help);
  END SetupPackage;

PROCEDURE SetupModule (loader: ObLoader.T) =
  BEGIN
    pkgloader := loader;
    pkgloader.load ("EmbProxiedObj.obl");
  END SetupModule;

*************************************************************************** Execution machinery ***************************************************************************

VAR errorException: ObValue.Val;

TYPE
  Code = {Error};

  OpCode = ObLib.OpCode OBJECT
    code: Code;
  END;

  Package = ObLib.T OBJECT
  OVERRIDES
    Eval := DoEval;
  END;

PROCEDURE DoEval (<* UNUSED *> self         : Package;
                  opCode       : ObLib.OpCode;
     <* UNUSED *> arity        : ObLib.OpArity;
     <* UNUSED *> READONLY args: ObValue.ArgArray;
     <* UNUSED *> temp         : BOOLEAN;
     <* UNUSED *> loc          : SynLocation.T) : ObValue.Val =
  BEGIN
    CASE NARROW (opCode, OpCode).code OF
    | Code.Error =>
      RETURN errorException;
    END;
  END DoEval;

*************************************************************************** Help ***************************************************************************

PROCEDURE Help (self : ObCommand.T; arg : TEXT; <* UNUSED *> data : REFANY) =
  BEGIN
    IF pkgloader # NIL THEN
      pkgloader.help (self, arg, pkgname);
    END;
  END Help;

VAR pkgloader: ObLoader.T := NIL;

BEGIN
END ObEmbProxiedObj.