Copyright (C) 1994, Digital Equipment Corp.
Digital Internal Use Only
Created on Wed Jul 20 09:48:11 PDT 1994 by najork
MODULE ObProxiedObj;
IMPORT ObAux, ObCommand, ObLib, ObProtoLoader, ObValue, Obliq, ProxiedObj,
SynLocation;
CONST
pkgname = "ProxiedObj";
***************************************************************************
Wrapper for ProxiedObj.T
***************************************************************************
REVEAL
T = Public BRANDED "ObProxiedObj.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) : ProxiedObj.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 ("Extend", 2, Code.Extend)
};
ObLib.Register (NEW (Package, name := pkgname, opCodes := opCodes));
ObLib.RegisterHelp (pkgname, Help);
END SetupPackage;
PROCEDURE SetupModule (loader : ObProtoLoader.T) =
BEGIN
loader.load ("ProxiedObj.obl");
END SetupModule;
***************************************************************************
Execution machinery
***************************************************************************
TYPE
Code = {Extend};
OpCode = ObLib.OpCode OBJECT
code: Code;
END;
Package = ObLib.T OBJECT
OVERRIDES
Eval := DoEval;
END;
PROCEDURE DoEval (self : Package;
opCode : ObLib.OpCode;
<* UNUSED *> arity : ObLib.OpArity;
READONLY args: ObValue.ArgArray;
<* UNUSED *> temp : BOOLEAN;
loc : SynLocation.T) : ObValue.Val
RAISES {ObValue.Error, ObValue.Exception} =
BEGIN
CASE NARROW (opCode, OpCode).code OF
| Code.Extend =>
WITH po = GetArg (args, 1, self, opCode, loc),
proxy = po.proxy DO
proxy.obj := Obliq.ObjectClone (Obliq.Vals {proxy.obj, args[2]});
RETURN proxy.obj;
END;
END;
END DoEval;
***************************************************************************
Help
***************************************************************************
PROCEDURE Help (self : ObCommand.T; arg : TEXT; <* UNUSED *> data : REFANY) =
BEGIN
ObAux.Help (self, arg, pkgname);
END Help;
BEGIN
END ObProxiedObj.