netobj/src/netobjrt/WireRep.i3

 Copyright 1992 Digital Equipment Corporation.               
 Distributed only by permission.                             
 WireRep.i3 
 Last modified on Sun Sep 25 18:44:29 PDT 1994 by heydon     
      modified on Mon Jul 19 14:46:12 PDT 1993 by wobber     
      modified on Wed Jun 10 17:14:36 PDT 1992 by owicki     


 The WireRep defines the network representation of network objects 
   and provides procedures to generate and manipulate values of this 
   type. 
   

INTERFACE WireRep;

IMPORT SpaceID, Word;

CONST Brand = "WireRep";

TYPE T = RECORD byte: ARRAY [0..15] OF BITS 8 FOR [0..255]; END;

CONST NullT = T {byte := ARRAY [0..15] OF BITS 8 FOR [0..255] {0, ..}};
CONST SpecialT = T {byte := ARRAY [0..15] OF BITS 8 FOR [0..255]
                         {255, 255, 255, 255, 255, 255, 255, 255, 0, ..}};

 A WireRep.T is a value which identifies a concrete network object. 
   In general, each T corresponds to one and only one real object 
   in a network.  Furthermore, each T is identifiable as having 
   been generated relative to a specific SpaceID.T.   However, there 
   are two well-known values which are exceptions to this rule.  The 
   value NullT corresponds to the NIL network object, and the 
   value SpecialT corresponds a {\it special object} which is a 
   distinguished concrete object in every address space.  This special 
   object is private to the implementation of the network object 
   runtime. 


PROCEDURE New() : T;

 Generates a new, unique WireRep.T value.  GetSpaceID(New() is
   equal to SpaceID.Mine(). 


PROCEDURE GetSpaceID(t: T) : SpaceID.T;

 Returns the SpaceID.T associated with the argument WireRep.T. 




 the following are for generic tables involving WireRep.T's 


PROCEDURE Equal(t1, t2: T) : BOOLEAN;
PROCEDURE Hash(t: T) : Word.T;

END WireRep.