Re: a clarification?

Michael Mealling wrote:

> Ok, I've been re-reading the namespace document again and some of the
> wording in other sections kind of bugs me a little based on these
> conversations.
>
> Specifically, http://www.w3.org/TR/1999/REC-xml-names-19990114/#dt-NSName
> " [Definition:] The attribute's value, a URI reference, is the namespace
>   name identifying the namespace. The namespace name, to serve its
>   intended purpose, should have the characteristics of uniqueness and
>   persistence. It is not a goal that it be directly usable for retrieval
>   of a schema (if any exists). An example of a syntax that is designed
>   with these goals in mind is that for Uniform Resource Names [RFC2141].
>   However, it should be noted that ordinary URLs can be managed in such
>   a way as to achieve these same goals."
>
> This definition seems to say to me: You can't assume that the namespace
> URI _always_ resolves to some resource but that it isn't prohibited either.
> And since it isn't prohibitied, I can build some infrastructure that
> requires it, correct?

I suppose it's a consistent position that some namespace names are OK according to
the namespace spec but not OK according to your infrastructure.

>  I personally wonder if the working group read the
> other documents produced by the URN IETF Working Group. Especially
> the ones that talked about URN resolution not being required for all
> spaces but also not prohibited for any either...
>
> Now, http://www.w3.org/TR/1999/REC-xml-names-19990114/#dt-identical
>   "[Definition:] URI references which identify namespaces are considered
>   identical when they are exactly the same character-for-character. Note
>   that URI references which are not identical in this sense may in fact
>   be functionally equivalent. Examples include URI references which differ
>   only in case, or which are in external entities which have different
>   effective base URIs.
>
> It seems to be that this document at least made the attempt to discuss
> our present problem(s). The question the document seems to leave
> unanswered is, what does it consider to be definitive:
> syntactic equivalence or functional equivalence?

Identicality [another stylistic abomination, but what the hell] is what's used in
the uniqueness test.  That leads to the question: what do you mean by "definitive",
and why does it matter if something is definitive or not?

Paul Abrahams

Received on Thursday, 1 June 2000 12:23:14 UTC