Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.csd.uwm.edu!gem.mps.ohio-state.edu!ginosko!uunet!cimshop!davidm From: cimshop!davidm@uunet.UU.NET (David S. Masterson) Newsgroups: comp.lang.c++ Subject: Re: Objectifying incoming messages? Keywords: type-server Message-ID: Date: 22 Aug 89 16:59:15 GMT References: <452@cimshop.UUCP> <444@cimshop.UUCP> <828@otc.otca.oz> Sender: davidm@cimshop.UUCP Organization: Consilium Inc., Mountain View, California. Lines: 22 In-reply-to: gregw@otc.otca.oz.au's message of 22 Aug 89 03:54:50 GMT >As I said before, I dont think this is the main issue with Objectifying >incoming messages. > Agreed, to a point. However, the need to objectify an incoming message is often the result of a outgoing request of some sort. So, the question of exitting a constructors and reentering constructors was more of "is there a proper arrangement for making requests that will facilitate processing replies without switch statements in C++?" >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. > Agreed. In C, there is the method of function call jump tables to get around massive switch statements. Is there such a thing as an object call jump table? (The return types would probably be different.) Could you define coercion of a base class into a derived class (the method still throws me)? David Masterson uunet!cimshop!davidm