[sugar] Multiple documents

[Yoshiki Ohshima]

  Eben,

> For on thing, Etoys refers to things as projects, which already sound like self contained bundles of sorts, much like a
> "sessions" in their own right.  Combining several projects in one session just complicates matters, when each can
> clearly be stored as its own entry within the Journal and resumed at will.  This is, after all, the basic model we're
> after.  But when, then, is it OK or even essential to break it?

  If the name matters, we can surely change it to call something like
"an Etoys document".  Don't think it as something so special; you can
probably think it as a slide in a presentation.

  Now, let us think a use case.  One document may store the thumbnails
of other documents, and you can open it when you click the thumbnail.
The actual target document may be in the same session (multiple
documents in one session) or fetched from Journal/disk (ah, this is
also multiple documents in one session, because you would like to keep
the sequencer document in the session).  That is essentially the way
to go through these slides in sequence right now.

  So, now, natural thing you would like to do is to make a sequence of
slides from two sequence of slides.  This is another use case.

  Anyways, please consider these use cases and let us know that what
would be a good way to fit them in the model.

-- Yoshiki