Ken --

You are right, in spite of the fact that the paper in question was 
really about the very first version of Playground, and was not "the 
later Playground" I was referring to in my note.
>
>What I want is a Playground-like system with real message sending,
>encapsulation, and removal of the limitation to only graphical objects.

This is what I want too. Let's just do one! At least a prototype. We'll help.

Cheers,

Alan


At 9:13 AM -0700 10/19/01, Ken Kahn wrote:
>Alan Kay wrote:
>>
>>  This is pretty much how Playground (the kids' programming system we
>>  made (mainly Scott Wallace starting with a framework built by Jay
>>  Fenton) for the Vivarium project) worked as well -- though I'm sure
>>  it wasn't as clean as Ken's stuff (this is why I'm trying to convince
>>  him to put some of his ideas into Squeak).
>>
>>  Playground was kind of a generalized event-driven system that had
>>  objects which were kind of like a collection of generalized
>>  spreadsheet cells, completely concurrent, etc.
>>        This gave the kids state of objects to look at, but not
>>  call/return. Every value was a thread.
>>
>
>I just reread (for the third time in 12 years) the OOPSLA89 paper on
>Playground.
>
>http://portal.acm.org/citation.cfm?id=74891&coll=portal&dl=ACM&CFID=292547&C
>FTOKEN=54781325
>
>It is full of good ideas but AFAIK the ability of objects to communicate was
>very impoverished. It seems they mostly interacted via the Playfield - a
>planar surface where objects live. This is great for some purposes but is
>too limitted in my mind. Objects could also signal events and others could
>sense those events but it didn't seem as if this was a general message
>passing facility. (The paper provides too few details on event signalling to
>really see how general it was.)  Also it didn't seem to support strong
>encapsulation - an object could inspect the internals of other objects.
>
>What I want is a Playground-like system with real message sending,
>encapsulation, and removal of the limitation to only graphical objects.
>
>Best,
>
>-ken kahn ( www.toontalk.com )


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