Xref: utzoo comp.lang.c++:5556 comp.object:433
Path: utzoo!attcan!uunet!aplcen!samsung!cs.utexas.edu!milano!cadillac!vaughan@mcc.com
From: vaughan@mcc.com (Paul Vaughan)
Newsgroups: comp.lang.c++,comp.object
Subject: Re: Shippable C++ Objects (RFC)
Message-ID: <4042@cadillac.CAD.MCC.COM>
Date: 17 Nov 89 15:58:22 GMT
References: <CIMSHOP!DAVIDM.89Nov15101037@uunet.UU.NET> <31.UUL1.3#5109@pantor.UUCP>
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Reply-To: vaughan@mcc.com (Paul Vaughan)
Followup-To: comp.lang.c++
Organization: MCC VLSI CAD Program
Lines: 18
In-reply-to: richard@pantor.UUCP (Richard Sargent)


	"The object can reconstruct itself from the byte stream" requires
	that the object already exist. It still seems to me that you *have*
	to have a case statement somewhere which knows about all (interesting)
	object classes.

Suppose that in the byte stream there is some token that uniquely
identifies the class of the the object being transmitted.  Then that
token could be used to look up in a table a function to be called to
create such an object.  So, you don't have to have a case statement
(other techniques are possible), but you do have to somehow know of
all interesting classes.  A further technique would be to transmit a
pathname through the byte stream and to use that to dynamically load a
class definition.  It would still be important to have a table of the
classes that were already loaded.

 Paul Vaughan, MCC CAD Program | ARPA: vaughan@mcc.com | Phone: [512] 338-3639
 Box 200195, Austin, TX 78720  | UUCP: ...!cs.utexas.edu!milano!cadillac!vaughan