open source, xanadu, persistence and other things (was: Udanax ?)
Laurent Martelli
martelli@iie.cnam.fr
29 Oct 1999 03:23:12 +0200
>>>>> "Jecel" == Jecel Assumpcao <jecel@merlintec.com> writes:
>> > I had tested ZigZag a few weeks ago (it is not in a state that
>> > I would pay $25 for it) and found the ideas interesting. I
>> think > objects would handle what his cells do pretty well,
>> though.
>>
>> Cells and objects are completely irrelevant (a cell IS an
>> object). Links are everything. I'm not impressed with ZigZag,
>> but you have to understand it in order to understand Xanadu.
Jecel> David Ungar says the same thing about Self: that objects and
Jecel> object-oriented programming aren't good, but a bunch of
Jecel> linked objects and how they connect together - that is
Jecel> everything.
Jecel> I like to "think different" :-), so I liked to play with
Jecel> ZigZag. But when you think about it, there is no great
Jecel> different between saying that C3 follows C2 in the "weight"
Jecel> dimension in ZigZag, or having the relation weight(C2,C3) in
Jecel> Prolog, or have the "weightNext" slot of the C2 object refer
Jecel> to the C3 object...
Considering available OOL, this makes a very big difference, since the
slot belongs to C2. Adding another relation requires that you modifiy
C2, and that's not possible at run-time for most OOL. Creating a new
relation that refers to C2 does not have this problem.
--
Laurent Martelli
martelli@iie.cnam.fr