Take a look at how OpenDoc did its thing. THere's a more efficient OOP container available called "IronDoc," done by the guy who was maintaining the Bento container for Apple when OpenDoc was still going.
It should be possible to use the OD strategy to handle the saving of both Squeak morphics and non-Squeak compound documents, via IronDoc.
Unfortunately, the developer of IronDoc (Dave McCusker) stopped working on it for a while, over a year, and has only recently popped back up. His latest thing is an alternative language called "Mithril" with multiple syntaxes, but the project's pretty embroyonic. I would suspect that IronDoc isn't stable enough for anything but idle curiousity - McCusker himself labels it "vaporware".
See:
http://www.best.com/~mccusker/irondoc/irondoc.htm
It also has a rather amusing approach to web navigation.
-- Duane
=================================================== Duane Maxwell dmaxwell (at) entrypoint.com CTO http://www.entrypoint.com EntryPoint, Inc. (858)348-3040 FAX(858)348-3100
Information contained herein is my personal opinion and not necessarily that of EntryPoint. ===================================================
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