Path: utzoo!attcan!uunet!intercon!news
From: amanda@mermaid.intercon.com (Amanda Walker)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Multiple Inheritance for HandleObjects in C++
Message-ID: <2690BBDC.6A63@intercon.com>
Date: 3 Jul 90 15:38:03 GMT
References: <15132@reed.UUCP> <268BA8DC.4CD4@intercon.com> <37@hite386.UUCP>
Sender: usenet@intercon.com (USENET The Magnificent)
Reply-To: amanda@mermaid.intercon.com (Amanda Walker)
Organization: InterCon Systems Corporation, Herndon, VA
Lines: 24

In article <37@hite386.UUCP>, steve@hite386.UUCP (Steve Hite) writes:
> Amanda
> is losing me at the point "...method wrappers to connect the two inheritance
> chains".  I would need to see an example of this because I'm shooting blanks
> trying to visualize it.  

Sorry about that :-).  I guess I forgot to translate my thoughts into
English before I typed them in.  What I was suggesting is the same thing
Larry did: having a C++ object (let's call it "a") with HandleObjects as
instance variables (let's call them "b" and "c").  My phrase "method wrapper"
means that "a" has methods that invoke the corresponding method from "b" or
"c".  Since "a" is not actually a subclass of either "b" or "c", you have
to manually pass the methods along, instead of having it done automatically
by the inheritance tree built by the compiler & linker.

It's clumsier that "real" multiple inheritance, but it might be enough for
many applications...

--
Amanda Walker
InterCon Systems Corporation
--
"I can only assume this is not the first-class compartment."
	--Hitchhiker's Guide to the Galaxy