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Re: What is at the end of the namespace?

From: Andy Powell <a.powell@ukoln.ac.uk>
Date: Fri, 16 Nov 2001 08:03:13 +0000 (GMT)
To: "Roy T. Fielding" <fielding@ebuilt.com>
cc: www-talk@w3.org, uri@w3.org
Message-ID: <Pine.SO4.4.05.10111160739280.12888-100000@lamin.ukoln.ac.uk>
On Thu, 15 Nov 2001, Roy T. Fielding wrote:

> > Yes, URIs *may* denote abstract resources. No, HTTP URLs may *not*.
> Patrick, as an author of both of those specifications, I can
> definitively state that what you are saying does not match what I intended
> when I wrote the sections to which you have referred. 

thanks for this.  So, the intention of the sepcification was that http
URIs may be used to denote any resource (including an abstract resource)  
- i.e. anything that has identity?

I have to say, that as fairly naive reader, your wording doesn't obviously
align with your intention (for me!).  I'm sure that this is the source of
the confusion.  Again, the RFC says

--- cut ---
3.2.2 http URL

   The "http" scheme is used to locate network resources via the HTTP
   protocol. This section defines the scheme-specific syntax and
   semantics for http URLs.

   http_URL = "http:" "//" host [ ":" port ] [ abs_path [ "?" query ]]

   If the port is empty or not given, port 80 is assumed. The semantics
   are that the identified resource is located at the server listening
   for TCP connections on that port of that host, and the Request-URI
   for the resource is abs_path (section 5.1.2).
--- cut ---

Phrases like 'network resources' and 'the identified resource is located
at the server listening for TCP connections' certainly don't convey to me
the idea that the http URI can be used to denote 'anything that has

FWIW, I would really like to see your intended meaning clarified (in
writing) somewhere - perhaps in http://www.w3.org/TR/uri-clarification/ ?


> That does not
> necessarily mean that both working groups interpreted those same words
> in the same way that I intended, but as far as I am concerned you are
> speaking fantasy.
> The URI spec is specifically modeled on the properties of HTTP URLs
> and the properties of HTTP URLs are specifically designed to model all
> possible URI space, because both are necessary in order for HTTP to be
> usable for name resolution and gateways for all URI, including URN.
> ....Roy

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Received on Friday, 16 November 2001 03:03:21 UTC

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