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From: gregw@otc.otca.oz.au (Greg Wilkins)
Newsgroups: comp.lang.c++
Subject: Re: Objectifying incoming messages?
Keywords: Messages
Message-ID: <828@otc.otca.oz>
Date: 22 Aug 89 03:54:50 GMT
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Sender: news@otc.otca.oz
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davidm@cimshop.UUCP (David Masterson) writes:

> However, in C++, its not a good idea for a constructor function to
>return before the reply (and, therefore, the data) has been received.  Thus
>the C++ program is hung. So, my question is what is the appropriate C++
>fashion for constructing an object when the object construction may involve
>sending a message and getting a reply that you don't want to wait for?

The problem of  Objectifying incoming messages is a very large complex problem.
However I think you have invented an extra problem for yourself.  
If you cannot completely construct an object until a message is sent and
a reply recieved, then
I see the the solution is to construct a base class, this bass class
then sends the message to find out
which particular specialization it is and coerces itself to a derived
class when it recieves the reply.

As I said before, I dont think this is the main issue with Objectifying
incoming messages.  The main problem
is coming up with a general method for inserting/extracting type
information without big case statements.
The central type server (to which you send a querry and recieve your
type in reply) may be one solution, but
it appears that all it is achieving is moving the case statement
somewhere else and ignoring the problem of
placement of explicit type information.

gregw@otc.oz