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RE: I-D ACTION:draft-daigle-uri-std-00.txt

From: Henrik Frystyk Nielsen <frystyk@microsoft.com>
Date: Thu, 7 Sep 2000 09:36:33 -0700
Message-ID: <005901c018e9$cb363d70$fb4c1fac@redmond.corp.microsoft.com>
To: "Simon St.Laurent" <simonstl@simonstl.com>, <XML-uri@w3.org>
> >Resources are first class objects - you identify them using
> URIs. When
> >describing or talking about a resource, you use the URI to
> refer to that
> >resource.
>
> Do you really?  What resource exactly does the URI
> http://www.w3.org/1999/xhtml identify?

The resource identified by the URI "http://www.w3.org/1999/xhtml".

Just as well as "New York" identifies the city identified by the name "New
York"

> It seems, however, that we may have different manifestations
> based on the
> context within which a URI is used - and no clear picture at
> all of what
> the resource might actually be.

All names are relative to something. "New York" is relative - it can
expand to the city, the state, or maybe some other city somewhere in the
world. You therefore have to specify the context that you are working
within.

The context is defined by the name space. City names are often relative to
the region. DNS hostnames are relative to the Internet. Local filenames
are relative to the local filesystem.

> I'm tired of koans.

I am not trying to be tricky - it is not my fault that names (as well as
pretty much anything else in life) is relative and that it causes certain
complications when defining a shared naming syntax for all names as URIs
do.

> >I don't believe it mentions anywhere that you are describing
> URIs because
> >that wouldn't make sense.
>
> Then I suppose Namespaces in XML is foolish for using URI
> references in a
> fashion that ignores the resource (or fails to define the relationship
> between the namespace and the resource) entirely...

Not at all - it is exactly correct of NS to use URIs as identifiers only.
Just as well as when you see a URI on a bus you are not told anything
about whether you will get HTML or something else when resolving it.

> I'd like a simple baseline definition for what exactly that
> == is supposed
> to be, and what != would be, without requiring reference to
> every document
> describing a scheme.
>
> Section 6 of RFC 2396 is inadequate in circumstances where
> applications
> must deal with URIs of more than one scheme - especially if those URIs
> don't "use elements of the common syntax".  I'll take byte-by-byte or
> case-insensitive as a foundation happily, but it has to apply
> across the
> board.  It clearly doesn't, at present.

For "elements of the common syntax", the equality operation is defined by
RFC 2396. For everything else, you use case-sensitive matching.

Henrik
Received on Thursday, 7 September 2000 12:35:47 GMT

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