xml-dev - XSchema Spec - XSchema Element (Sections 2.0 and 2.1), Draft 4

["Simon St.Laurent" <SimonStL@classic.msn.com>]

This is the latest version of the XSchema element.  Namespaces now must appear 
before element and notation declarations.  I've attempted to clear up some of 
the language surrounding the XSchema specification version and XSchemas 
created using that specification.

Major Question: Do we want Attribute declarations allowed outside of element 
declarations?  If yes, we need to do that here.  This will be fairly minor 
surgery; the AttDef element will also need a new attribute for its parent 
element.  The XML 1.0 spec doesn't have any such production - it just uses 
Name.

As always, a prettier HTML version of this will be posted shortly at 
http://purl.oclc.org/NET/xschema.

Simon St.Laurent
Dynamic HTML: A Primer / XML: A Primer / Cookies

2.0 XSchema Syntax

This section describes the XSchema document syntax. The XSchema document is an 
XML document containing a single XSchema element in which information 
describing the schema is nested. The XSchema element must be preceded by an 
XML declaration and may be preceded by other declarations, comments, and 
processing instructions.

2.1 The XSchema Element

The XSchema element is the root element for all XSchema documents. The 
declaration for the XSchema element is:

<!ELEMENT XSC:XSchema (XSC:Doc?, XSC:More?, XSC:Namespace? (XSC:ElementDecl | 
XSC:Notation | XSC:XSchema)*)>
<!ATTLIST XSC:XSchema
    Version CDATA #FIXED "1.0"
    MimeType CDATA "application/xml"
    FileExtension CDATA "xml">

The XSC:XSchema element contains other elements describing the XSchema and 
building a schema. These elements are described in later sections of this 
specification. The XSC:XSchema element may also contain other XSC:XSchema 
elements nested inside of it.

The XSC:XSchema element's attributes include information about the version of 
the XSchema specification used as well as information about the type of 
documents described by the XSchema. 

Information about the XSchema specification version used to create this 
XSchema, contained in the XSC:Version attribute, is critical to proper 
handling of documents should the specification be updated in the future. This 
specification is identified as version 1.0. Future major and minor versions of 
the XSchema specification should identify themselves differently. No provision 
is made at this time for nesting XSchemas using different versions of the 
specification under a parent XSchema element.

The XSC:MimeType and XSC:FileExtension attributes are used to provide a 
suggested MIME (Multipurpose Internet Mail Extensions) Content-type and file 
extension for documents created using a particular XSchema. Applications may 
use this information to identify XML document types. A document library that 
generates XML documents dynamically could assign file extensions and MIME 
types based on the XSchema used. 

Applications using this information should use the values stored in the first 
XSchema encountered during processing. For instance, if an XSchema includes 
another nested XSchema, the values for the XSC:MimeType and XSC:FileExtension 
attributes of the root XSchema should be used.

By default, most XML documents are assumed to have a MIME type of 
application/xml, as described in "XML Media Types" by E.J. Whitehead and 
Murata Makoto. Developers who need different MIME types for documents created 
using particular XSchemas may register other MIME types with the IETF, as 
described in RFC 1590, or use the 'x-' prefix syntax for subtypes, as 
described in RFC 1521.


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