Inheritance/defaulting of attributes

[Matthew Fuchs]

On Oct 9, 10:59am, Paul Prescod wrote:
> Subject: Re: Inheritance/defaulting of attributes
> Rick Jelliffe wrote:
...
> > A push for OO constructs for element declarations actually creates
> > a new distinction between declarations and the instance: the
> > declarations would act by inheritance and magic and the document
> > acts by text replacement: or is there some meaningful extension of
> > inheritance to include instance data?
>
> My proposal from yesterday does this.
>
> <!ELEMENT animal EMPTY>
> <!ELEMENT (shark|lion) ISA animal)
>
> <!ELEMENT zoo (animal+)>
>
> <ZOO>
> <SHARK/>
> <LION/>
> </ZOO>
>

Note that you have come up with new syntax to do something which in SGML would
be handled through minimization, i.e., something like:

<!entity % animals " shark | lion ">
<!element (%animals;) - O empty>
<!element animal O O (%animals;)>
<!element zoo - - (animal+)>

The parser would then interpolate <animal> tags around each <shark> or <lion>
tag, allowing the application to understand a relationship not obvious in the
document text.  (OK, so I also used parameter entities.  So sue me.)

Matthew

-- 
-----------------------------------------------------
Matthew Fuchs
matt at wdi.disney.com
http://cs.nyu.edu/phd_students/fuchs
-----------------------------------------------------

xml-dev: A list for W3C XML Developers. To post, mailto:xml-dev at ic.ac.uk
Archived as: http://www.lists.ic.ac.uk/hypermail/xml-dev/
To (un)subscribe, mailto:majordomo at ic.ac.uk the following message;
(un)subscribe xml-dev
To subscribe to the digests, mailto:majordomo at ic.ac.uk the following message;
subscribe xml-dev-digest
List coordinator, Henry Rzepa (mailto:rzepa at ic.ac.uk)