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Comment by shalabhc | Hacker News Reader

> and the next phase of this would have been much closer as a "deep" extensible language.

Are these ideas (and the 'address space of objects') elaborated on somewhere?

> A data structure is something that allows fields to be "set" from the outside. This is not a good idea. My original approach was to try to tame this, but I then realized that you could replace "commands" with "requests" and imperatives with setting goals.

I agree with in principle - but I'm having trouble imagining computing completely without data structures though (and am reading 'Early History of Smalltalk' to see if it clicks.)

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You need to have "things that can answer questions". I'd like to get the "right answer" when I ask a machine for someone's date of birth, and similarly I'd like to get the right answer when I ask for their age. It's quite reasonable that the syntax in English is the same.

? Alan's DOB

? Alan's age

Here "?" is a whole computer. We don't know what it will do to answer these questions. One thing is for sure: we are talking to a -process- not a data structure! And we can also be sure that to answer the second it will have to do the first, it will have to ask another process for the current date and time, and it will have to do a computation to provide the correct answer.

The form of the result could be something static, but possibly something more useful would to have the result also be a process that will always tell me "Alan's age" (in other words more like a spreadsheet cell (which is also not "data" but a process)).

If you work through a variety of examples, you will (a) discover that questions are quite independent of the idea of data, and (b) that processes are the big idea -- its just that some of them change faster or slower than others.

Add in a tidy mind, and you start wanting languages and computing to deal with processes, consistency, inter-relations, and a whole host of things that are far beyond data (yet can trivially simulate the idea in the few cases its useful).

On the flip side, you don't want to let just anybody change my date of birth willy nilly with the equivalent of a stroke of a pen. And that goes for most answers to most questions. Changes need to be surrounded by processes that protect them, allow them to be rolled back, prevent them from being ambiguous, etc.

This is quite easy stuff, but you have to start with the larger ideas, not with weak religious holdovers from the 50s (or even from the way extensional way math thinks via set theory).

Thank you for the elaboration!

(And for anyone else reading this thread I found an old message along the same topic: http://lists.squeakfoundation.org/pipermail/squeak-dev/1998-...)

I'm thinking along these lines now: decompose systems along lines of 'meaning', not data structures (data structures add zero meaning and are a kind of 'premature materialization'), design messages first, late bind everything so you have the most options available for implementation details, etc.

The other thing I'm thinking is why have only one way to implement the internal process of an object/process? There are often multiple ways to accomplish goals, so allow multiple alternative strategies for responding to the same message and let objects choose one eventually.

Edit: wanted to add that IIUC, 'messages' doesn't imply an implementation strategy - i.e. they are messages in the world of 'meaning'. In the world of implementation, they may just disappear (inlined/fused) or not (physical messages across a network), depending on how the objects have materialize at a specific point in time.

You've got the right idea. If you think about how services on the internet operate, they don't have one way of implementing their internal processes, either.

I finally got the idea, after listening to Kay for a while, that even what we call operating systems should be objects (though, as Xerox PARC demonstrated many years ago, there is a good argument to be made that what we call operating systems need a lot of rethinking in this same regard, ie. "What we call X should be objects."). It occurred to me recently that we already have been doing that via. VMs (through packages such as VMWare and VirtualBox), though in pretty limited ways.

Incidentally, just yesterday, I answered a question from a teacher on Quora who wanted advice on how to teach classes and methods to a student in Python, basically saying that, "The student is having trouble with the concepts of classes and methods. How can I teach those ideas without the other OOP concepts?" (https://www.quora.com/Can-I-explain-classes-and-objects-with...) It prompted me to turn the question around, and really try to communicate, "You can teach OOP by talking about relationships between systems, and semantic messaging." If they want to get into classes and methods later, as a way of representing those concepts, they can. What came to mind as a way around the class/method construct was a visual environment in which the student could experience the idea of different systems communicating through common interfaces, and so I proposed EToys as an alternative to teaching these ideas in Python. I also put up one of Kay's presentations on Sketchpad, demonstrating the idea of masters and instances (which you could analogize to classes and object instances).

I felt an urge, though, to say something much more, to say, "You know what? Don't worry about classes and methods. That's such a tiny concept. Get the student studying different kinds of systems, and the ways they interact, and make larger things happen," but I could tell by the question that, dealing with the situation at hand, the class was nothing close to being about that. It was a programming class, and the task was to teach the student OOP as it's been conceived in Python (or perhaps so-called "OOP". I don't know how it conceives of the concept. I haven't worked in it), and to do it quickly (the teacher said they were running out of time).

The question has gotten me thinking for the first time that introducing people to abstract concepts first is not the right way to go, because by going that route, one's conceptions of what's possible with the idea become so small that it's no wonder it becomes a religion, and it's no wonder our systems don't scale. As Kay keeps saying, you can't scale with a small conception of things, because you end up assuming (locking down) so much, it's impossible for its morphology to expand as you realize new system needs and ways of interacting. The reason for this is that programming is really about, in its strongest conception, modeling what we know and understand about systems. If we know very little about systems that already exist, their strengths and weaknesses, our conception of how semantic connections are made between things is going to be very limited as well, because we don't know what we don't know about systems, if we haven't examined them (and most people haven't). The process of programming, and mastering it, makes it easy enough to tempt us to think we know it, because look, once we get good enough to make some interesting things happen (to us), we realize it offers us facilities for making semantic connections between things all day long. And look, we can impress people with that ability, and be rewarded for it, because look, I used it to solve a problem that someone had today. That's all one needs, right?...

Kay has said this a couple different ways. One was in "The Early History of Smalltalk". He asked the question, "Should we even teach programming?" Another is an argument he's made in a few of his presentations: Mathematics without science is dangerous.

(also, for the benefit of anyone else reading this thread, the following section written in 1993 talks more about these ideas: http://worrydream.com/EarlyHistoryOfSmalltalk#oostyle)

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