RE: [w3c sml] [4688] Consider using xml:base

I agree with Sandy's proposal. It is good to use xml:base since it is a w3c recommendation and is meant for that purpose.

From: public-sml-request@w3.org [mailto:public-sml-request@w3.org] On Behalf Of Sandy Gao
Sent: Tuesday, September 11, 2007 6:59 AM
To: public-sml@w3.org
Subject: RE: [w3c sml] [4688] Consider using xml:base


> ... not sure what the second bullet does or
> why it is needed.  As long as modelType has anyAttribute on it,
> which it should - if not that is a bug to be opened, xml:base can
> already be freely used and will validate, no?

Schema declarations for xml: attributes are not "built-in", so we at least need an <import> for the "xml" namespace. After that, whether there is an explicit reference to xml:base in "modelType" doesn't make any difference, for schema assessment purposes. (Assuming we change "skip" to "lax" for the attribute wildcard on "modelType".)

The only reason I thought we needed the explicit reference was that the current <baseURI> element applies to the entire IF document. But if we go with xml:base, then I agree that we shouldn't make the "global scope" any different from other places where xml:base could be used.

So amended proposal:

- Remove smlif:baseURI
- <import> the "xml" namespace
- Use infoset [base URI] property in places where "smlif:baseURI" is currently used.

It may also be helpful to explain how [base URI] works and how it's computed; at least with a pointer to the infoset spec, and possibly to xml:base spec.

Thanks,
Sandy Gao
XML Technologies, IBM Canada
Editor, W3C XML Schema WG<http://www.w3.org/XML/Schema/>
Member, W3C SML WG<http://www.w3.org/XML/SML/>
(1-905) 413-3255 T/L 969-3255


public-sml-request@w3.org wrote on 2007-09-10 06:50:40 PM:

>
> I'm sorry but from the enclosed interleaved email thread(s?) I
> cannot reliably figure out exactly what proposal it is we are
> assessing for agreement.  With a non-HTML mail client eg what
> someone gets searching the archive, it is much worse.
>
> If it is the one below (Sandy...So counter-proposal: ) then I am ok
> with it at first blush, but not sure what the second bullet does or
> why it is needed.  As long as modelType has anyAttribute on it,
> which it should - if not that is a bug to be opened, xml:base can
> already be freely used and will validate, no?
>
> Sandy...So counter-proposal:
> - Remove smlif:baseURI
> - Add a reference to xml:base in "modelType" (to allow <model xml:base="...">)
> - Use infoset [base URI] property in places where "smlif:baseURI" is
> currently used.
>
> Best Regards, John
>
> Street address: 2455 South Road, Poughkeepsie, NY USA 12601
> Voice: 1+845-435-9470      Fax: 1+845-432-9787
>

>
> Pratul Dublish <Pratul.Dublish@microsoft.com>
> Sent by: public-sml-request@w3.org
> 09/07/2007 01:38 PM
>
> To
>
> "public-sml@w3.org" <public-sml@w3.org>
>
> cc
>
> Subject
>
> RE: [w3c sml] [4688] Consider using xml:base
>
>
>
>
> All (except Sandy J)
>
> Please speak up now if you disagree with Sandy's proposal. You may
> want to read my comments on Sandy's proposal.
>
> Thanks!
> Pratul
>
> From: Sandy Gao [mailto:sandygao@ca.ibm.com]
> Sent: Friday, September 07, 2007 8:58 AM
> To: Pratul Dublish
> Cc: public-sml@w3.org
> Subject: Re: [w3c sml] [4688] Consider using xml:base
>
>
> Pratul and all,
>
> > 1.       <baseURI> allows attribute extensions, and this will be
> > lost if xml:base is used
>
> Yes, and the rest of the XML world has lived with that for many
> years. (xml: id, lang, base, ... are all attributes)
> [Pratul] Members should consider what is best for SML.  We should
> avoid gratuitous divergence from existing standards but we should
> feel free to define new things if required.
>
>
> > 2.       The xml:base spec uses the definition of URI from RFC 2396
> > but the definition of xs:anyURI in XML Schema 1.0 uses RFC 2396 as
> > amended by RFC 2732. So there is a possibility (I don't know for
> > sure since I haven't read 2396) that xml:base is not aligned with xs:anyURI
>
> There's some weirdness in the xml:base spec. It only mentions 2396
> in most cases, but also mentions 2732 in one place.
>
> Yes, it's possible to have such inconsistency, but this would happen
> between any 2 specifications we reference. For example, if XPath 1.0
> and Schema 1.1 are used together; ...
>
> (This one feels even weaker, because 2732 really isn't much
> different from 2396.)
> [Pratul] I found that XML Base has issued an Errata (http://www.w3.
> org/2001/06/xmlbase-errata) that switches to the definition of URI
> in RFC3986. This is consistent with SML and SML IF specs - both of
> which reference RFC 3986.  We already have the possibility of
> inconsistency with XML Schema 1.0 since it uses RFC 2396 as amended
> by RFC 2732.
>
>
> > 3.       xml:base does not support IRIs, so it can't be used if we
> > decide to support IRIs in SML IF ( bug 4632  )
>
> It does support IRIs in a way similar to anyURI. xml:base allows
> non-ASCII characters; its values, after escaping, become valid URIs.
> [Pratul] My point was that xml:base does not follow the IRI RFC (3987).
>
>
>
> So I don't see any of the above as significant problem. On the other
> hand, reinventing an existing concept, which is widely supported
> (including infoset), seems more problematic to me.
>
> So counter-proposal:
> - Remove smlif:baseURI
> - Add a reference to xml:base in "modelType" (to allow <model xml:base="...">)
> - Use infoset [base URI] property in places where "smlif:baseURI" is
> currently used.
>
> Thanks,
> Sandy Gao
> XML Technologies, IBM Canada
> Editor, W3C XML Schema WG
> Member, W3C SML WG
> (1-905) 413-3255 T/L 969-3255
>
>
> public-sml-request@w3.org wrote on 2007-09-07 12:28:00 AM:
>
> > All
> > This is an attempt to instigate consensus on the resolution of this
> > bug. We don't have any specific proposal for this bug, so I am going
> > to make a proposal based on my comments in the bug. The proposal is
> > that SML IF should not use xml:base and continue to use the existing
> > <baseURI> element because
> >
> > 1.       <baseURI> allows attribute extensions, and this will be
> > lost if xml:base is used
> > 2.       The xml:base spec uses the definition of URI from RFC 2396
> > but the definition of xs:anyURI in XML Schema 1.0 uses RFC 2396 as
> > amended by RFC 2732. So there is a possibility (I don't know for
> > sure since I haven't read 2396) that xml:base is not aligned with xs:anyURI
> > 3.       xml:base does not support IRIs, so it can't be used if we
> > decide to support IRIs in SML IF ( bug 4632  )
> >
> >
> > Please speak up now if you disagree with this proposal.
> >
> > Thanks!
> > Pratul