Paul Fernhout wrote:
>
> Eric Armstrong wrote:
>
> > I'm interesting if *any* encoding system would solve the problems
> > you mention.
>
> No XML-ish scheme can....
>
Ignoring XML and anything remotely like it. What would you use?
> ...
> The point is to create a DKR/OHS flexible enough to deal with this
> issue of representations changing over time as users needs change.
>
How?
> And to take things further, why invent XML when one could instead just
> use LISP to the same effect (and with less bytes)? Lisp is used all
> the
> time to define representations such as:
> (user
> (ID 100001)
> (name "Grampa Muenster")
> (address "13 Mockingbird Lane"))
>
If we're only talking about data representations, this could easily
be done in XML. One is not required to use DTD-validation when parsing
an XML structure. So one can easily add other name/value pairs, without
being constrained by a DTD. The only time a DTD comes into play is when
you *want* to enforce restrictions. And there are times when you want
that.
> Lisp can easily parse this which defines a valid LISP list, and we can
> define LISP programs with related data that validate such
> representations. That is what AI programmers have been doing for
> decades.
>
Certainly. Validating the structure is always possible in the program,
with Lisp, XML, or any other data representation. DTD-validation is only
a convience that permits taking that burden off the programmer, when it
is desirable. There is also an intermediate ground. An DTD can be
written so that any number of pairs of name and value elements can
occur, so what you see is
<name>ID</name><value>100001</value><name>address</name>... etc.
The DTD can then ensure that the name/value pair restriction is never
violated, but the values can be anything we want. Again, validation is
not required, so even this restriction does not have to be enforced.
> However, in my opinion, the investment in learning and
> using these other systems (Smalltalk, Lisp) is worth it.
>
No argument there. Maybe some of the flexibility you desire comes from
the ease of manipulation in those languages, rather than from the data
structures themselves?
------------------------------------------------------------------------
LOW RATE, NO WAIT!
Get a NextCard Visa, in 30 seconds! Get rates
as low as 2.9% Intro or 9.9% Fixed APR and no hidden fees.
Apply NOW!
http://click.egroups.com/1/2122/3/_/444287/_/954821718/
------------------------------------------------------------------------
Community email addresses:
Post message: unrev-II@onelist.com
Subscribe: unrev-II-subscribe@onelist.com
Unsubscribe: unrev-II-unsubscribe@onelist.com
List owner: unrev-II-owner@onelist.com
Shortcut URL to this page:
http://www.onelist.com/community/unrev-II
This archive was generated by hypermail 2b29 : Mon Apr 03 2000 - 21:22:36 PDT