Re: [xml-dev] My report on experiments with unused namespaces

["Pete Cordell" <petexmldev@codalogic.com>]

Original Message From: "Michael Kay"

> W3C doesn't make laws, it writes specifications. Don't read a W3C spec to 
> discover whether document is legal or illegal.

I think the original poster used 'legal' so I went with that.  I probably 
mean "well-formed",  and, if applicable, "namespace-well-formed".

> Documents using names beginning "xml" are not illegal; they are not even 
> ill-formed; they simply contain names that are reserved. It's up to you 
> whether documents containing reserved names are acceptable in your 
> application or not.

By reserving names that start with "xml" I'm assuming the W3C is saying that 
you (anyone not acting on behalf of the W3C) can not define names that start 
with "xml".

If this weren't the case, surely this paragraph should have been a Note 
similar to that about colons in names that follows it, and say something 
like:

    Note: Names beginning with the string "xml", or with
    any string which would match (('X'|'x') ('M'|'m') ('L'|'l')),
    _may be used_ for standardization in this or future versions
    of this specification.  Therefore, authors should not use the
    XML names beginning with "xml" except as described by
    relevant W3C specifications.

So an XML instance that contains an xmlns attribute MUST be using the 
definition of that attribute defined by the W3C as no one else is allowed to 
define such an attribute, and since there is only one place where such an 
attribute is defined, it MUST be a namespace declaration.

So, even though the application _reading_ the XML might not be XML namespace 
aware, the application _creating_ the XML containing an xmlns... attribute 
MUST be namespace aware (otherwise it's broken - for some value of broken!) 
and therefore the attribute MUST be a valid namespace declaration, even if 
the reading application doesn't know that.

Pete Cordell
Codalogic Ltd
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