Re: Context info for datatype libraries

[Murata Makoto <mura034@attglobal.net>]

James Clark wrote:

> Surely parsed entity declarations are part of the document.  How can you
> allow parsed entity declarations but disallow the XML version number
> without exhaustively enumerating all the things in the document that you
> are going to allow access to? And I certainly don't want to do that.
> 
> Incidentally, I think accessing the version number is perfectly
> reasonable.  Suppose the set of name characters changes in some future
> version of XML.  Why shouldn't a datatype library have a datatype that
> accepts a NCName, where what a NCName is depends on the XML document it
> occurs in?

I certainly want to "exhaustively enumerat(e) all the things in the document 
that you are going to allow access to".

Do you want to allow data type libraries to access absolutely anything 
in the document?  For example, is it OK for a datatype libary to access to 
the DOM representation of the entire document?  Unless I am convinced that 
enumeration is impossible or very difficult, I am not willing to open 
the back door.

Your example about version numbers is quite persuasive.   Here is my list.

	- prefix-URI mappings
	- base URIs
	- XML version numbers
	- entity declarations
	- xml:lang (which may be inherited)

We also have to consider  "Document Information Item" of XML Information Set. 

>>>>>>

[notations] An unordered set of notation information items, one for 
each notation declared in the DTD. 

[unparsed entities] An unordered set of unparsed entity information 
items, one for each unparsed entity declared in the DTD. 

[base URI] The base URI of the document entity. 

[character encoding scheme] The name of the character encoding scheme 
in which the document entity is expressed. 

[standalone] An indication of the standalone status of the document, 
either yes or no. This property is derived from the optional standalone 
document declaration in the XML declaration at the beginning of the 
document entity, and has no value if there is no standalone document 
declaration. 

[version] A string representing the XML version of the document. 
This property is derived from the XML declaration optionally present 
at the beginning of the document entity, and has no value if there is 
no XML declaration. 

[all declarations processed] This property is not strictly speaking 
part of the infoset of the document. Rather it is an indication of 
whether the processor has read the complete DTD. Its value is a 
boolean. If it is false, then certain properties (indicated in their 
descriptions below) may be unknown. If it is true, those properties 
are never unknown. 

<<<<

Cheers,

Makoto