[net.lang.st80] beyond Smalltalk

kdmoen (02/24/83)

In his thought provoking article on Smalltalk in the September 1977
issue of Scientific American, Alan Kay wrote:
	"   The third and newest framework for high-level communication
	is the observer language.  Although message-activity
	languages are an advance over the data-procedure framework,
	the relations among the various activities are somewhat
	independent and analytic.  Many concepts, however, are so
	richly interwoven that analysis causes them to virtually
	disappear.  For example, 20th-century physics assigns equal
	importance to a phenomenon and its context, since observers
	with different vantage points perceive the world differently.
	In an observer language, activities are replaced by 'viewpoints'
	that become attached to one another to form correspondences
	between concepts.  For example, a dog can be viewed abstractly
	(as an animal), analytically (as being composed of organs,
	cells and molecules), pragmatically (as a vehicle by a child),
	allegorically (as a human being in a fairy tale) and contextually
	(as a bone's way to fertilize a lawn).  Observer languages are
	just now being formulated.  They and their successors will be
	the communication vehicles of the 1980's."

Can anyone explain this to me?  Has anyone actually devised an
'observer language'?  The closest things that I can think of are
those languages that support sub-classes with multiple inheritance.
For instance, the class 'dog' might inherit properties from the
super-classes 'animal', 'pet', 'allegorical-being', etc.

Speaking of multiple inheritance, I have heard that a package supporting
multiple inheritance has been written for Smalltalk-80.  Does anyone
have details?

I have also heard rumours of an applicative dialect of Smalltalk.
If this is true, then I am particularly interested in hearing about
how the problem of dealing with interactive i/o is dealt with, and
whether applicative Smalltalk is actually nicer to use.  Again,
if anyone has any information, please mail me or post it.

	Doug Moen, watmath!kdmoen

henry (03/19/83)

When speculating on what sort of things Alan Kay was talking about in
his Scientific American article, bear in mind that Scientific American's
editors are said to have altered Kay's article to the point where he
disavows responsibility for the published version.