[cells-devel] Re: Usual Tiltonspeak rebuttal (was Re: ILC 2005...)

Kenny Tilton ktilton at nyc.rr.com
Wed Jul 6 17:14:44 UTC 2005



Joerg Hoehle wrote:
> Kenny Tilton <ktilton at nyc.rr.com> writes:
> 
>>But no user has ever indicated they could not figure out how to 
>>program with Cells, despite the absence of documentation.
> 
> 
> Well, me, and I've casually listened to cell-speak since the days
> where it was called semaphors and Kenny Tilton was still aiming at
> enlightment :)
> -- Now K.Tilton is going to Killton me.
> 
> More concretely, I did not groked the concept of "be". To be or
> become, that is the question.

And Kenny refused to answer your question when you emailed him? The bastard!

> 
> More precisely, I think I understand the abstract requirement, as it's
> nothing new and seen in many places, e.g. the separation between
> constructing parts of pipeline, clunging it together and finally have
> something flow through the pipes, but the spare explanations in what
> doesn't want to call itself cells documentation confuse me more than
> help.

Well, the problem is making the quantum leap from not being in the 
dataflow to being in the dataflow all at once. Some background:

One of the nice things about Cells is that the models which are driven 
by them can vary in population without worrying much about those 
transient moments when the model is only partially constructed or 
destructed. For example, I can add instances A and B to the model, where 
A has a slot with a rule which asks B for a slot with a rule which asks 
A for a different slot value, and everything Just Works. This is 
possible because of a certain JIT, on-demand quality of Cells, and 
because entry or exit from the model by any given instance is managed by 
to-be and not-to-be.

There is (or was) even some code in the internals that gave special 
handling to the crucial "kids" slot of the Family class, which is what I 
always use to build complex models. I think advances in Cells II 
obviated the need for that special handling. I also think the special 
handling of the kids slot /outside/ the internals should be generalized 
so other slots with the same model-extending semantics can be easily 
defined by non-expert users.

The main idea behind to-be is (a) taking care of initialization required 
by Cells internals and (b) getting an instance across that quantum leap 
  from not being in the flow to being in the flow.

re the latter, suppose I push a new model instance onto the KIDS of some 
Family instance in a working model. The idea behind Cells is automatic 
state consistency, but we now have an instance whose rule-mediated slots 
are unbound, and whose slot values, once calculated, have not been 
manifested outside the model by any "output" methods which may exist.

to-be takes care of evaluating ruled slots and outputting all 
cell-mediated slots.

-- 
Kenny

Why Lisp? http://lisp.tech.coop/RtL%20Highlight%20Film

"If you plan to enter text which our system might consider to be 
obscene, check here to certify that you are old enough to hear the 
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