7 Questions on DCDs
Roger L. Costello
costello at mail11.mitre.org
Tue Jan 12 16:11:36 GMT 1999
(1) Will a DCD have a DOCTYPE declaration, or is that a thing
of the past?
(2) XML instance documents will specify the the DCD it is
conforming to using namespaces, rather the using the DOCTYPE
declaration?
i.e., instead of:
<?xml version="1.0"?>
<!DOCTYPE BookCatalogue SYSTEM
"file://localhost/xml-course/xml-part1/BookCatalogue.dtd">
<BookCatalogue>
...
</BookCatalogue>
it will be:
<?xml version="1.0"?>
<BookCatalogue xmlns="file://localhost/xml-course/xml-part1/BookCatalogue.d
cd">
where in BookCatalogue.dcd I must have:
<?xml version="1.0"?>
<DCD>
<Description>DCD to define a Book Catalog</Description>
<Namespace>file://localhost/xml-course/xml-part1/BookCatalog
ue.dcd</N amespace>
<ElementDef Type="BookCatalogue" Model="Elements" Root="true">
...
</DCD>
(3) Will it make sense to validate a DCD? If so, how? Should
a DCD document reference the DCD namespace (to enable validation)
e.g.,
<DCD xmlns="http://www.w3.org/TR/NOTE-dcd.html">
...
</DCD>
(4) The examples in the DCD spec use the RDF namespace (e.g., RDF:Order)
but no where is a namespace declaration shown. Should there be
a namespace declaration for the RDF prefix?
i.e.,
<DCD xmlns="http://www.w3.org/TR/NOTE-dcd.html"
xmlns:RDF="http://www.w3.org/TR/NOTE-rdf.html">
...
</DCD>
(5) It is not clear to me how to define an attribute whose
datatype is an enumeration and is required. In DTD it is
specified as:
<!ATTLIST Book
Category (autobiography | non-fiction | fiction) #REQUIRED>
I am guessing that in DCD it is specified as:
<ElementDef Type="Book" Model="Elements">
<AttributeDef Name="Category" Datatype="enumeration"
Occurs="Required">
autobiography non-fiction fiction
</AttributeDef>
...
</ElementDef>
(6) What's the difference between an ElementDef with Content="Open"
versus an ElementDef with Model="Any"? They seem to mean the
same thing.
i.e., <ElementDef Type="foo" Model="Mixed" Content="Open"> ...
versus
<ElementDef Type="foo" Model="Any"> ...
(7) Can somebody explain this external entity example:
<ExternalEntityDef resource="#copyrightNotice"/>
Where did this copyrightNotice thing come from?
Thanks. /Roger
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)
More information about the Xml-dev
mailing list