language: toward Obliq

dufrp at dufrp at
Sun Aug 30 11:33:11 UTC 1998

Although I do like to read this mailing list I do not use a lot Squeak
mainly because I have a small&slow computer which is using mostly DOS
as an operating system. Which means I have to borrow my sister big
computer to use Squeak (a 486DX4-100, HD 512Mb).

I'd like to find a modern combo language+OS that doesn't take much to
be run and for now it seems it's going to be Oberon, but I use to
change of language or programming language almost every week. :-)

First I'd like to tell that the BNF grammar of Squeak that was posted
here recently did looked pretty usefull for someone wishing to learn
Squeak, without any needs to add more semantical information. Such a
BNF grammar is a great reference when learning a new language.

I like the ability to explore Squeak with the browsers. I did also
like to see the multiple message dispatching of Smalltalk. But like I
said before I don't use it much, and the only program I wrote in
Squeak was a small 'Guess my number' game that was writing on
Transcript and reading numbers from FillInTheBlanks. I was trying to
make all this in one window, when I was beginning to explore the MVC
concept and I did get lost there and was not trying much harder at
Squeak ever since. Although most others GUI must be using controllers
I never have seen them before using Squeak. I suppose others language
and GUI are simply hiding them.

Since it seems that Squeak is, with the 'language and polymorphism'
thread, thinking about how to make itself better, this was making me
to think about a message I read here about the future of Squeak that
could become be more expressive by using new ideas proposed by
researcher Luca Cardelli.

Although that Cardelli is using a mathematical formalism that I don't
really understand, I do have my way of understanding his ideas and I
would summarize them in two ideas. First an objects is a bunch of
fields, and this fields can all be changed. A field can be any value,
including, and that what is new, a method value. So an object can
modify his methods or add new ones.

Second idea: an object can be cloned. So rather than using classes the
way we do with Smalltalk, we can create a function that clone a base
object and return it.

This seems to give much more expressive power, and with it the
possibility to make code that is much more harder to read and
understand. Anyway my feeling is that it is worth it.

Cardelli have made a language (in 1995?) that is using these concepts
and add the idea that you can also make an assignment not only to
local fields (normal values or methods values) but also to fields of
objects on remote computers, making this way a distributed language.

This language is called Obliq. It is distributed with an other
language in which it was implemented: Modula-3. Modula-3 take about
1Gb of hard disk space and that much much more than I have. So I never
saw Modula-3 neither than I saw Obliq.

I'd like to ask if there is someone working at making Squeak using
these ideas. This could well be the case because I read about Cardelli
here some months ago.

Cardelli have also wrote a not so funny paper about user interface. It
seems also that Obliq is using a powerful user interface looking like
Visual Basic. Maybe Squeak could be one day using such an interface
that would maybe be simpler than current MVC model?

Since that the original thread was about what's polymmorphism I'd like
to say that Cardelli have also wrote one or two papers describing what
it is.

>From memory, I would say that the web page of Cardelli is: (but my browser seems to make a bad request.)
Maybe the easy way is to follow the links from Yahoo on Obliq.

I am not saying Squeak should follow this path. I guess Obliq have a
mystical look to me because I have not really seen it yet. Somehow I
guess I am trying to have others use it so that they can tell me if it
is as good as I amagine it. :-)

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