Peter at ursus.demon.co.uk
Fri Apr 11 19:27:02 BST 1997
Thanks very much - it's becoming clearer, and at least I've got the direction
correct :-). But I'm not clear what quantities are inherited...
For discussion assume that the declarations belong to MYDTD
In message <199704111037.GAA00242 at localhost> David Megginson writes:
> <?ArcBase html?> <?ArcBase math?>
So in C++ terms MYDTD has two base classes, HTML and MATH.
> [notations and entities omitted]
> <!ELEMENT para ...>
> <!ATTLIST para
> html NAME #FIXED "p">
This means that PARA (in MYDTD) inherits properties from P (in HTML). Does
that mean it automatically inherits the content model and the attributes?
For example, the content model of P is
which expands to
(#PCDATA | IMG | BR | EM)* <!-- several missed out -->
Can PARA assume these or does it have to map each of these (e.g. IMG) onto
<!ELEMENT image ...>
html NAME #FIXED "img>
similarly does PARA have to explicity declare the same attributes as P in HTML?
> <!ELEMENT fraction ...>
> <!ATTLIST fraction
> math NAME #FIXED "frac">
> <!ELEMENT sym ...>
> <!ATTLIST symbol
> html NAME #FIXED "sym"
> math NAME #FIXED "symbol">
This is - presumably - multiple inheritance in that SYMBOL inherits something
from HTML.SYM and MATH.SYMBOL (though I'm not clear what). How does the
content of SYMBOL relate to either of its two base classes?
Peter Murray-Rust, domestic net connection
Virtual School of Molecular Sciences
xml-dev: A list for W3C XML Developers
Archived as: http://www.lists.ic.ac.uk/hypermail/xml-dev/
To unsubscribe, send to majordomo at ic.ac.uk the following message;
List coordinator, Henry Rzepa (rzepa at ic.ac.uk)
More information about the Xml-dev