FromNess, ToNess

[Mark S. Miller <mark>]

Date: Tue, 30 Jan 90 10:24:13 PST
   From: bobp (Bob Perez)

   I've been meaning to ask this for some time: what advantages are there 
   (both for us and for the developer community) in releasing B&O? Apart from
   N-ended links, what features do we anticipate getting used?

One can think of the Berts & Orgls layer as attempting to provide low
level semi-direct access to the powers of the Ent in a way consistent
with secure asyncronous distributed multi-party use.  The Docs & Links
layer makes a *LOT* of policy choices about particular ways we think
are useful to use that power.  When Docs&Links are the only Febe
interface, our users are locked into those policy choices.  With
Orgls&Berts exposed, they can do Docs&Links like systems of their own.

This was quite important to me when I defined the initial Docs&Links
layer--I had much less confidence that it was correct than I did with
Orgls&Berts.  Therefore it was important to insure that our product be
quite valuable even if others think that our Docs&Links layer isn't
good.

I still agree with all the above as a design philosophy (provide both
the most general low level *mechanism* you can, as well as a default
*policy* for its use); however, since Ravi took over Docs&Links, my
anxiety about its quality has disappeared.

What is now the important consideration is that users/developers will
be able to do things quite different than Docs&Links with Orgls&Berts.
I don't know what those things are, but I do know there's a lot of
power there that Docs&Links aren't using.  I know this is all very
vague & fuzzy, but if I had figured out compelling interesting things
to do with Orgls&Berts, those things might have made it into
Docs&Links.  

John Walker has an ammusing story about experience with users of
AutoCad utilizing multiple layers in unexpected ways (which he might
relate if he sees this.  John?).  The story helps remind one to design
general degrees of freedom even if you can't forsee what they're
useful for.  Note that this isn't the same as providing lots of
widgets whose utility is questionable.