- From: Gignac Donald A CRBE <GignacDA@nswccd.navy.mil>
- Date: Tue, 20 Mar 2001 13:42:22 -0500
- To: "'www-xml-schema-comments@w3.org'" <www-xml-schema-comments@w3.org>
- Cc: "Westbrook Evelyn L (Lori) CRBE" <WestbrookEL@nswccd.navy.mil>, Junod L J II CRBE <JunodLJ@nswccd.navy.mil>
1. The "XML Schema schema for XML Schemas: Part 2: Datatypes" does not parse against the schema DTD with the identifier "-//W3C//DTD XMLSCHEMA 200102//EN". This is because that the 's' parameter entity
<!ENTITY % s ''>
defined in the external subset results in the "xmlns" attribute being defined twice for the "schema" element type. This is due to fact that the
<!ENTITY % s ''>
defined in the external subset takes precedence over the
<!ENTITY % s ':xs'>
defined in the internal subset. This results in the replacement text of the "nds" parameter entity
<!ENTITY % nds 'xmlns%s;'>
being defined as 'xmlns'. This causes the 'xmlns' attribute to be defined twice for the 'schema' element type
<!ATTLIST %schema; ...
%nds;
xmlns CDATA #IMPLIED ... >
since the 'p' parameter entity is defined as
<!ENTITY % p ''>
in the external subset and the 'schema' parameter entity is defined as
<!ENTITY % schema '%p;schema'>
in the external subset.
2. I propose the following changes to remedy this situation. Introduce the 'xmlns-prefix' parameter entity
<!ENTITY % xmlns-prefix "%nds; %URIref; #FIXED 'http://www.w3.org/2001/XMLSchema'">
into the exterior subset (i.e., the "structures" DTD) after the definition of the 'nds' and 'URIref' parameter entities. Then change the
'%schema;' ATTLIST declaration from
<!ATTLIST %schema; ...
%nds;
xmlns CDATA #IMPLIED ... >
to
<!ATTLIST %schema; ...
%xmlns-prefix;
xmlns CDATA #IMPLIED ... >
Since "at the Infoset level where schemas operate, the xmlns(:prefix) is NOT an attribute", the first "xmlns" attribute definition can be removed from the '%schema;' ATTLIST by redefining the 'xmlns-prefix' parameter entity as
<!ENTITY % xmlns-prefix "'">
in the interior subset (i.e., the DOCTYPE declaration subset).
Donald Gignac 301-227-3348 "gignacda@nswccd.navy.mil"
Received on Tuesday, 20 March 2001 13:43:07 UTC