W3C | TAG | Previous: 11 Nov teleconf | Next: 25 Nov teleconf

Minutes of 18 Nov 2002 TAG face-to-face meeting

Nearby: Teleconference details issues list www-tag archive

1. Administrative

  1. Roll call: SW (Chair), TBL, TB, NW, DO, DC (Afternoon), CL, PC, IJ (scribe), Martin Duerst (Morning). Regrets: RF
  2. Did not yet accept 4 Nov minutes
  3. Accepted this agenda
  4. Next meeting: 25 Nov teleconf.
  5. No meetings: 23, 30 December.

1.1 Completed actions

1.2 February meeting

The TAG may reschedule its February meeting (both days and location). Follow-up on the TAG list.

1.3 Presentation at W3C AC meeting

The TAG reviewed slides for its presentation at the W3C Advisory Committee meeting (Nov 2002).

2. Technical

2.1 URIEquivalence-15, IRIEverywhere-27

  1. IRIEverywhere-27
    1. See reply from Paul Grosso asking the TAG to address this issue quickly.
  2. Status of URIEquivalence-15. Relation to Character Model of the Web (chapter 4)? See text from TimBL on URI canonicalization and email from Martin in particular. See more comments from Martin.
    1. CL 2002/08/30: Ask Martin Duerst for suggestions for good practice regarding URI canonicalization issues, such as %7E v. &7e and suggested use of lower case. At 16 Sep meeting, CL reports pending; action to send URI to message to TAG.
[Ian]
SW: Time for a finding?
TB: I think we are ready for a finding on matching semantics.
CL: There are tough issues (e.g., proxy caches, etags) in different communities. I'd like to declare some issues out of scope so we can get quick agreement on smaller sets.
TBL: I think we need to explain where IRIs fit in architecturally. My understanding is that there's a URI space and an IRI space, and a function that maps from one to the other. We can talk about equality among URIs, and we can talk about mappings from IRI -> URI. We need to point out that IRIs are a way to talk about URIs (like relative URIs map to absolute ones).
TBL: We are not changing the URI space by talking about IRIs. There is not a function from URIs to IRIs.
CL: Why would someone want to go from URIs to IRIs?
MD: Sometimes you go to URIs to early.
CL: But that's a repair issue.
TBL: People *will* want to display URIs in IRI syntax.
[Chris]
rrsagent, pointer?
[RRSAgent]
See http://www.w3.org/2002/11/18-tagmem-irc#T14-44-48
[Ian]
MD: If you define some URIs to be very strictly equivalent in all cases (including namespace matching) it makes it natural to define some IRIs to be equivalent to those URIs in all cases. Suppose U1 is equivalent to U2. It makes a lot of sense to say that I3 is always equivalent to them.
TB: It's not, unless you fix the % escape case matching.
[Chris]
I suspected they were not equivalent, but wanted to be clear
[Ian]
TBL: If IRIs stand for URIs, then comparing IRIs doesn't make sense. You always talk about equivalence of URIs.: I advise you strongly to not redefine HTTP and MAILTO for IRIs...
CL: To compare I1 and I2, you have to convert them and compare U1 and U2.
[Discussion about escaping]
TBL: We can give you a set of circumstances under which you can know that two URIs are the same. You know that if URIs are byte-by-byte equivalent, they are the same. We can add to that canonicalization of %7e and %7E. There are other things you can know from other specs that lead to equivalence. We should say "don't rely on that other stuff".
[Chris]
CL was asking a question of TimBL not stating a position
[Ian]
TBL: We suggest you use the same byte sequence for the same URI.: Basically, don't be clever.

TB: Three ways to test URI equivalence:

  1. "Schema-specific canonicalization and comparison" (e.g., HTTP URIs with normalizing on "..").
  2. "RFC2396-based canonicalization". (e.g., maximum canonicalization, or lightweight canonicalization such as canonicalization of hex escapes)
  3. Compare ASCII character values.
TB: All of these are potentially reasonable (though (c) is most questionable). The namespace Rec says "character by character" comparison, so there's some ambiguity. In any sane universe %7e and %7E are the same character. At the very least, we should document the multiple levels of comparision, and document the application contexts where it would be reasonable to do these things. And we strongly recommend that specs be entirely specific about what they require.
TBL: NO! URI equivalence is not spec-specific. Equivalence is not a property of other specs.
TB: You can't make the judgment calls go away. It's perfectly ok to not be sensitive to HTTP-specific issues when you're dealing with general URIs.
SW: Different degrees of "equivalence". There are many equivalence relationships.
TBL: String identity is the highest form of equivalence in our context. If you have string identity, it implies every other form of equivalence. Expanding circles are: ascii string THEN %7e <=> ~ THEN %7e <=> %7E THEN ".." and "." THEN HTTP/DNS THEN SMTP, etc. ...
[Chris]
<foo bar="HelloWorld"/>
<foo bar="Hello&#x57;orld"/>
<foo bar="Hello&dubya;orld"/>
[Ian]
TB: I think most appications would throw on the floor and xml doc with a namespace with W3.ORG in uppercase.
CL: If the value of bar is "any URI", are those three the same? I think so, since they are the same strings after XML processing.
[Chris]
after xml parsing al three are the safe and will match under option 3
[Unanimous]
[Ian]
IJ: Should the TAG say "Do up to and including level X?"
TBL: Since practice varies we should not tell people they can rely on level 3.
TB: But we could tell people for future practice to do a particular level.
[Chris]
[Discussion on 2396 and whether it does foo/../bar canonicalization]
TBL: relative uris require that /../ must be equivalent to /
SW: want to see this explicit
TB: RF is fixing this we believe
[timbl]
TBL: RFC2396 dioes indeed not say that xxx/./yyy is equivalnet to xxx/yyy fopr any xxx and yyy. However, the only tenable situation is that they are equivalent. because we require that any URI can be relative-ized and absolute-ized back to its original. That is an (unspoken) axiom.
When you relative-ize things and re-absolutize then, you cannot distinguih between the two, and so they HAVE to be equivalent. The URI spec should say that.
Resolved: unanimously (except for IJ, who stepped out of the room).
[Ian]
TB summarizing:
  1. we should talk about mapping from IRIs to URIs and URI-based equivalence testing. Show the Venn diagram of URI comparison levels.
  2. We may have agremeent about levels of Venn diagram that specs should say.
  3. Explain drawbacks of doing different levels.
[Chris]
Should also indicate strengths and drawbacks of different choices
[Ian]
IJ: What does this mean for XML Namespaces? What story would you tell?
TB: I think it would be helpful to tell the core group which level to use. Meanwhile, I don't think we can say when to use IRIs since they're not baked yet.
IJ: But we can tell them how they fit in./
CL: I think we can respond to initial query. We can tell people to plan on using IRIs when they're done.: We can tell people to design specs to use URIs, but to prepare for the introduction of IRIs. Tell them how to not paint themselves into a corner.
NW: The XML Core WG is trying to decide what to put into the next version of the namespaces spec. They have a capsule summary of what IRIs are, to be replaced by a ref to the IRI spec later. I can't tell from the discussion here whether we are telling the core WG if it's ok to do what they're doing.
Initial questions from Jonathan Marsh
Action TB: Write a finding for URIEquivalence-15 on IRI relation to URI, different levels of equivalence.
TBL: If a spec transitions from URIs to IRIs, new documents will break old software (which used to only handle URIs). Typically, what happens is that user agents evolve but authors SHOULD NOT use the new stuff for a while. We could tell people that it's ok for the software to accept IRIs but authors should not use them for a while.
SW: I think we need a thought-out transition plan.
CL: "anyURI" in the XML Schema spec is already IRI-ready.
IJ: Specs should not handle this differently. Can we give them text for their documents?
MD: Some specs may have to do this differently.
NW: People use "stringcmp" to compare namespace strings.
SW: What should our response to Jonathan Marsh be?
TB proposal:
  1. We view IRI activity with favor.
  2. Software should prepare for IRIs
  3. IRI spec not done, practices such as XML 1.0 sys id seem to be reasonable, but they need to figure out how to bring themselves into sync with IRIs when they become available.
MD: I agree that developers need to think about the transition issue.
TBL: We can't tell people what's best to do for their applications (since so many variables, policies, etc.). We can describe the framework.
CL: We need to explain the risk of not moving to IRIs: proprietary approaches if IRIs not adopted.
PC: XML Query has an "anyURI-equal" funtion. Described as being on a "codepoint-by-codepoint" basis.
PC: If you are looking for behavior of anyURI, don't look in schema, look in query. See XQuery definition of an op:anyURI-equal function See XQuery definition of an op-resolve-uri function.
[timbl]
TB, please point to the layer of the onion which corresponds to schema:anyURI.Equal()
[Ian]
PC: See Functions and Operators.
NW: For namespaces 1.1, the backwards-compatibility issue already exists. It's safe to say "they can be IRIs"; breaking software is probably not a huge issue yet.
TBL proposal:
  1. Specs (e.g., an XML application) that use Unicode should call out IRIs.
  2. Refer to the upcoming IRI spec, which we hope will stabilize soon.
  3. Warn people that authors should stick to URIs during a transition period, that will vary according to their transition period.
CL: Namespace 1.1 should say that a particular usage is being brought up to date with other usage.
TBL: We need to write down the axioms: if you take a URI, make it relative w.r.t. a base URI, then make it absolute w.r.t. the same base URI, you get the same starting URI...
CL: I think the finding should explain pros and cons as we said above, what people with old specs should do, and what people with new specs should do.
Action MD: Write up text about IRIEverywhere-27 for spec writers to include in their spec.
Action CL: Write up finding for IRIEverywhere-27 (from TB and TBL, a/b/c), to include MD's text.

2.2 Architecture Document

See also: findings.

  1. Findings in progress:
    1. deepLinking-25
      1. TB 2002/09/09: Revise "Deep Linking" in light of 9 Sep minutes. Status of finding?
  2. Arch Doc
    1. Continued action CL 2002/09/25: Redraft section 3, incorporating CL's existing text and TB's structural proposal (see minutes of 25 Sep ftf meeting on formats).
    2. Completed action NW 2002/09/25: Write some text for a section on namespaces (docs at namespace URIs, use of RDDL-like thing). Done
    3. Continued action DC 2002/11/04: Review "Meaning" to see if there's any part of self-describing Web for the arch doc.

See 15 November 2002 Architecture Document. See some comments from Tim Bray.

[Ian]
TB: In the principles, the distinction between "constraints", "practices", and "principles" still needs work. Perhaps we can move
simply to "practices" and "principles" - it's really unclear that "Use URIs" is really different in its nature from a bunch of things labeled "practices".
[Some disagreement from CL, TBL on this]
TB: The principles in 2.2.4 and 2.2.5 are really the same principle. The explanatory text in 2.2.5 is just a rehash of the Moby Dick example.
IJ: I can explain why this was done: I have been trying to distinguish case of "representations that vary inconsistently" and "meaning of use" discussions.
TBL: Previous draft for me was too vague. Too general to say that "ambiguity is a bad thing". To say that a mailto URI identifies a book is wrong. The RFC says different. To couch that as ambiguity is wrong. One spec owns the definition.
TB: In the real world, the marketing dept and the IT dept may use URIs internally differently.
SW: What about namespace names. We are expecting to put documents at the end of the namespace URI. In RDF, how do I make assertions about the document and assertions about the namespace.
TBL: You have to be able to deal with the different levels.
TB summarizing:
  1. We agree that ambiguity is bad.
  2. When dealing with these things, you follow specs (e.g., don't use mailto URIs to identify things other than mailboxes).
SW: The generic statement is "follows specs".
IJ: Please confirm that there is some authoritative meaning; I can only understand ambiguity w.r.t. some reference.
TB: The arch of the web talks about resources and representations.: 2.2.4 as written is ok. It implies inconsistency in identity of resource. The other issue is that using the web in a way that goes against specs is wrong.
IJ: You can use mailto uris to talk about mailboxes. I presume you can also use http URIs.
TBL: Not to refer mailboxes as defined by RFC 2368
TB: Ambiguity is bad, on server or client. Don't fly in the face of specs.
TBL: We need to also highlight *design choices* in the architecture document.
TB: Two other suggestions: Arguing about the range of URIs will not be useful right now. I have some proposals for sections 3 and 4.
DO: I think we haven't resolved yet what are the components of this document (constraints, principles, etc.).
[Chris]
3.4 third list item "Allow for Web-wide linking, not just internal document linking." I would like to discuss that as low hanging fruit.
[Ian]
Discussion ofproposals from Tim Bray.
IJ: I am not currently working on a "model" that fits together constraints, principles, etc. Too hard to rip up the document at this time.
PC: I think a glossary of those terms would be useful.
IJ: The terms I had listed were: constraint, principle, design choice, good practice, required property.
TB: Sections 3 and 4 have been languishing. We should just start putting in nuggets and then fill in with language around them.
Proposed CP1 "When designing a data format to be used in representing Web Resources, the use of XML should be considered carefully. - some issues concerning XML pros and cons, - refer to IETF 'Guidelines for the Use of XML within IETF Protocols'."
CL: That document does describe pros and cons.
IJ: Add XML Accessibility Guidelines for use of XML in protocols doesn't talk about accessibility.
Action IJ: Send notes to TAG with comments on using xml.
Resolved: Add CP1 to spec.
Proposed CP3 "When specifying the use of URIs, designers SHOULD NOT constrain the
use of URI schemes."
TBL: In some constrained applications, you may want to e.g., constrain to some class of URNs.
CL: What about something like "You must support the HTTP protocol on this element, and may support others".
TBL: Yes, that's ok.
[Chris]
Except for phones that haver no http stack?
[Ian]
Resolved: Add CP2 to spec. Provide a counter-example.
Proposed CP3: "When using XML, designers SHOULD NOT introduce syntax constraints beyond those involved in the definition of XML."
CL: Different specs impose additional syntactic constraints (e.g., namespaces).
TB: E.g., what SOAP did about not having an internal subset is wrong. SOAP imposes a severe cost (you can't use an off-the-shelf XML parser). You can't enforce the SOAP constraints by using off-the-shelf products.
DO: I disagree with the principle.
TB: There's a big difference between profiling, and saying "you can use single quotes only but not double quotes".
Resolved: CP3 rejected as proposed.
Proposed CP4: "XML-based languages MUST be given a namespace name and the elements of the language MUST be placed in that namespace. Designers SHOULD make available a representation of the namespace which is human-readable and SHOULD make available a representation which is a machine-readable directory of resources which are related to that namesapce."
Amendment: "XML-based languages for widespread common use MUST be given a namespace name and the elements of the language MUST be placed in that namespace."
PC: What about data types and functions?
TB: There's room for argument about things other than elements; there are other design choices.
PC: An XML-based language might have other components. Does the arch doc not need to make statements about those other components?
TB: XML namespaces only refers to elements and attributes, not other types of things.
Amendment: "XML-based languages for widespread common use MUST be given an XML namespace name and the elements of the language MUST be placed in that namespace."
TBL: I agree with TB's more specialized statement, but I think that important resources such as those functions and operators need to be identifiable by URI.
[Discussion that TAG has not yet agreed on all of second sentence of CP4.]
Resolved: Accept "XML-based languages for widespread common use MUST be given an XML namespace name and the elements of the language MUST be placed in that namespace."
SW: Can it draw on elements from other languages?
TB: If you important elements from another language, that's fine.
TBL Proposed: "If you are designing and XML language, in which the required functionality is available from elements in another namespace, there is benefit from the reuse those elements."
CL: There's a problem of content types.
General agreement for a statement encouraging the reuse of previously defined elements where appropriate.
CL: I had wanted style properties to be in a namespace....
TB: CL, I suggest you write down a principle.
Proposed CP5: " For languages whose contents are intended for rendering to humans, the repertoire of formatting semantics SHOULD be consistent across the universe of W3C recomnmendations."
Resolved: Accept CP5, with examples (e.g., style sheets). Link to relevant finding (and similarly for other of these proposals).
Proposed CP6: "When designing a language that includes linking or hypertext functionality, designers SHOULD design that functionality so it supports Web-side rather than merely local linking."
CL: About CP6 - in SVG you can point from a fill to a gradient. We could have made this an idref, but we made it a link so you can reuse gradients.
TB: Another way to say this is "Don't use IDREF"....
DO: In SOAP, they use ID and IDREF.
NW: Does anybody here disagree with CP6?
Resolved: Accept CP6.
Proposed CP7:"Designers of languages which will be used in resource representations MUST arrange for the registration of an Internet Media
Type for that language, and SHOULD consider the recommendations of RFC3023 in carrying out that registration. This registration MUST include a specification of the handling of fragment identifiers for resource representations in the language being designed."
[TB notes that we have a finding on this.]
CL: Note that "+xml" does not define fragment semantics.
TB: I don't think we should rely on default semantics. Be explicit if you expect to change semantics later.
DO: Indicate that there is no default fragment identifier semantics for XML.
TBL: See RFC3023: "As of today, no established specifications define identifiers for XML media types. However, a working draft published by W3C, namely "XML Pointer Language (XPointer)", attempts to define fragment identifiers for text/xml and application/xml. The current specification for XPointer is available athttp://www.w3.org/TR/xptr."
CL: My worry is not that the spec doesn't say something....
DO: If XPointer goes to Rec, will RFC3023 be revised?
TB: Even if XPointer goes to Rec, that doesn't help much. You don't know what ID elements are unless you have a DTD.... For CP7, the point is "read RFC3023 and think about it."
Action CL: Incorporate resolutions above into a proposal for chapter 3. [Scribe presumes this supersedes previous action from 2002/09/25]

LUNCH

DC arrives.

[RRSAgent]
See http://www.w3.org/2002/11/18-tagmem-irc#T18-32-01
[Ian]
Resolved: Accept CP7 with language about warning about no default meaning for frag ids. [See below for amendment.]
DC: WebOnt WG is currently wondering what media type to use. Owl? I conclude that application/rdf+xml is the right thing
TB: You should arrange for the registration "unless one existst that you can use."
[Question: "What MIME type should I use?"]
TBL: If you know that the XML app is going to dispatch on the root element, you can use text/xml with impunity. RF pointed out that for the infrastructure, it's useful for, e.g., SVG, to have its own mime type. We agreed that it's better to dispatch on the mime type.
[Chris]
... where the best choice is an existing media type
[Ian]
DC: I think that CP7 will lead to more questions from WGs.
TB: I think it's useful to say that languages at W3C should have mime types unless there's really a good reason not to.l
Resolved: In CP7, say "SHOULD arrange" instead of "MUST arrange".
Proposed CP8: "Designers of languages which are to be interchanged on the Web MUST include a discussion of error-handling, with specific recommendations on the correct behavior upon detection of certain classes of errors. - example classes: XML well-formedness vs. semantic brokenness (eg SVG circle with negative radius)"
CL: SVG spec can't revise error handling of XML spec, though.
DC: What about general principle about being liberal in what you accept and conservative in what you produce?
CL: No.
DC: Then I object to this point.
TB: RFC3023 includes some discussion of this.
[DanC]
The word "liberal" does not occur in RFC3023.
[Ian]
DC and CL agree that the liberal/conservative Internet principle should be mentioned because IT IS NOT universal.
[Chris]
"Forbid working around xml well-formedness"
[Ian]
IJ: I find CP8 too broad.
DC: No, there's something more basic: Don't silently throw away error messages.
TBL: It only makes sense to define processing where the protocol gives you some guarantee through the processing.
CL: SVG has error-handling.
TB: I think W3C specs shouldn't advance if they don't discuss error-handling.
DC: To me, the core principle is about evolvability or scalability.
Resolved: CP8 rejected as proposed.

2.3 RDDL, namespaceDocument-8

See 8 Nov 2002 version of RDDL from TB and Jonathan Borden and issue namespaceDocument-8.

[Ian]

TB: RDDL goes back several years. Some principles: (1) be human-readable (2) be able to find style sheets and schemas and other stuff. Need metadata: (1) purpose and (2) nature. I should be able to say "Get me an xml schema" and use the metadata in the RDDL document to find one (or one from several, according to additional purpose or nature constraints). Natures and purposes are URIs. nature-> xlink:role, purpose->xlink:arcrole
Some disputes about that choice. I created a RDDL in RDF draft. But some people pointed out that this was done in a way that wasn't kosher.
[Chris]
this is an ongoing discussion n xml dev
what should we do?
already committed to write a note, using rdddl, could have the xlink encoding or the rdf
in the latter case, lots more discussion needed
or use another RDDL namespace
first draft should do all three and discuss
dc: use cases where this would help?
tb: ms office 11 stores everything as xml, it is al well formed and uses namespaces heavily
also, stop using urns, use http instead and point to persistent urls and point to schemas
RDDL would be handy for this
point to stylesheets, .net etc etc
dc: why not point to these from the schema?
cl: same reason as not pointing to the schema from the .net everyone wants to be top
so a neutral, easy to parste format to point to these
dc: why mix them up
tb: because the one url serves this
dc, tbl: use coneg
tbl: or put in html, advantage is mixomg metadata and html
tbl; many sites do not do coneg anyway
[TBray]
also many people who publish to webservers don't have control of the conneg settings on the server
[PaulC]
Latest Q&A on MS Office 11 XML support.
[Chris]
cl: cause for concern of using a multi-namespace xml design in a system (html browser) that is not xml
dc: html wg should be part of the design
skw: who is the authorship of this
tb: jb and i to publish as a w3c note
do: wsdl havea requireent to identify the elements that are semantically interesting. If a document is replicated, it no longer has a unique uri. Namespace name is consistent across these representations.
[DanC]
reviewing minutes from Sep ftf, we didn't decide anything about RDDL; we just actioned TB to propose something.
[Chris]
do: Want to use ns name as base uri for these constructs, eg port type. How to write a uri reference that identifies the port type? without ids. Don't want to generate ids for all elements. NS name of the service, append the construct
[do draws on whiteboard]
piza delivery web service
wsdl specifies interface info (astract) and physical deployment
two pizza shops have to publish at different urls
do: so .... multiple users of one wsdl file, all clients have the same instance
no single master url for this document
this is the 'locally stored copy' issue
only common thing is the namespace url of the service
they did GET copies
just, not every time they want a new pizza
[DanC]
er... he said the didn't. or at least: I heard that.
[Chris]
do: so they want a wsdl-specific xpointer scheme - but that depends on the media type, so we cant use this inside a xhtml document in there
[DanC]
(it's sooo frustrating paying the cost of not just using RDF)
[Chris]
so need to dereference through the rddl document to their scheme
dc: ok I see the problem
tbl: not a problem unless you use html. RDF uses barenames not xpointer schemes, but also appends onto namespace names, but keeps the same ns name for all the multiple copies
[Ian]
TBL: There's a solution - say that for HTML elements, # refers to element, but for WSDL, refers to a real-life thing.
[Chris]
skw .wsdl means you could have a separate media type
dc: but rddl in the middle would break that connection
[Ian]
DO: If we go down RDDL path, we need to define frag id semantics.
[Chris]
tb: he wants t point into his rddl doc using his xpointer scheme
cl; ok, but that means he can only point to wsdl documents
[dc writes on whiteboard]
dc: schema for html block elements. Schema for p, p extends block, etc.
urlofdoc#p
no, because urlofdoc#style
is that the style elemnt or the style attribute?
xptr can point into this
RDF answer is to ensure its a directed labelled graph
then, turn the crank and get the syntax
pc: does not solve the anonymous types issue
nw: nun ensures that all the anonymous types have distinct uris
dc: so now we see the cost of wsdl not doing this
do: referring to wsdl issue 120 about unique adressability was raised by SW folks. WSDL has requirements above the requirements of SW.
[Roy]
I'm at ApacheCon in Las Vegas. No phone, but will hang out on IRC if there are any questions. [No opinion on RDDL]
[PaulC]
XML Schema Nun proposal (W3C member only)
[Ian]
Specific example from Jonathan Borden:

<rddl:resource ID="XSD">
<rddl:title>XML Schema</rddl:title>
<rddl:nature resource="http://www.w3.org/2001/XMLSchema"/>
<rddl:purpose resource="http://www.rddl.org/purposes#schema-validation"/>
<rddl:related resource="http://example.org/L.xsd"/>
<rddl:prose>
<p>An XML Schema for the L language .</p>
</rddl:prose>
</rddl:resource>

TB: I want to be able to reach into a RDDL document and find "purpose: validation". I want to be able to reach into a RDDL document and find "purpose of validation".

DC: In RDF you would say "purposes:validation". Nature and purpose are not symmetric.
TBL: The community mismodeled nature and purpose.
TB: Whenever you put in something more complicated than http://lists.xml.org/archives/xml-dev/200211/msg00719.html, people get unhappy.
[DanC]
<rddl:resource ID="XSD">
<rddl:title>XML Schema</rddl:title>
<rddl:nature resource="http://www.w3.org/2001/XMLSchema"/>
<p:schema-validation resource="http://example.org/L.xsd"/>
<rddl:prose parseType="Literal">
<p>An XML Schema for the L language .</p>
</rddl:prose>
</rddl:resource>

[Ian]
PC: Schema WG has rejected using namespace name for locating frag ids. Sounds like multiple WGs tackling same problem with different solutions.
[PaulC]
XML Schema Designator of Schema (Member only)
[DanC]
p is http://www.rddl.org/purposes#
[Ian]
TB: Jonathan suggested what DC suggested.
DC: Problem with the RDDL approach is that I can't cut and paste directory entries (or merge them).
[DanC]
The "implicit" design contradicts the "anyone can say anything about anything" principle of RDF
[Ian]
CL: But we *are* talking about namespace docs, so the namespace URI is implicit.
DC: But the namespace doc is a common place to look for it. It doesn't mean that you shouldn't be able to copy it and preserve the meaning. You could change "id" to "about' and put the namespace there.
PC: Perhaps we need some more time to discuss this.
TB: Note that http://lists.xml.org/archives/xml-dev/200211/msg00719.html has received a lot of support. We should not make more complicated than we need. Dan's representation is more accurate.
NW: If you are using predefined purposes, you could avoid extra namespace.
TB: DC's version makes purpose less obvious. RDDL was sold to the world as having nature and purpose.
CL: I propose that the first draft show different possible syntaxes, with their pros and cons.
PC: I think that the work done on this by Schema (Member-only) is material to this discussion.
TB: For the record, I promoted RDDL as a way to do a 2-field lookup. I'm not going to be in favor of requiring any bending over backwards to accomplish this effect.
[DC proposal]
Suppose L is a namespace about lunch. Namespace URI: http://example.com/L. There are two related resources: L.xsd and L.css.
TB: L.xsd is a nature (xml schema) and a purpose (for validation).
[DC does circles and arrows graph, a facsimile of which is below. See also SVG and dot]

Circles and arrows graph of Lunch namespace

TB: Add a CSS style sheet as well. Purpose is "Onscreen presentation". There's a reserved word for that in RDDL... The nature of the style sheet includes IANA stuff, and more...(Arguably there's a better way to do this).
DC: Two resources are related by "purpose".
TB: Sample application - build a menu of available actions in a RDDL document. I'll buy DC's graph. However, using RDF syntax I would need an RDF engine.
DC: So we need to pick one syntax.
TBL: We could propose a canonical xml serialization of RDF.
CL: application/rddl+rdf?
TB: That's a hard problem, too..
CL: We have two contradictory principles for W3C specs - you need to validate v. mixing multiple namespaces.
TB: I personally think RDDL is important. I think we need to converge quickly on a suggested right way to do this.
Action TB: Solicit proposals for what a namespace doc should look like for the particular case of a namespace document that refers to a DTD and a style sheet. TB will collate the responses. TB's solicitation should ask submitters for their own pros and cons.
Action NW: Take a stab at indicating pros and cons for the various designs.

2.4 Linking, xlinkScope-23

Seeissue xlinkScope-23.

[Ian]

PC: What's our next step?

TBL: I think there's a clear need for a common anchor element in the XLink namespace.
NW: Content model problem....
CL: OBJECT has three URIs and two bases. Can't use xbase.
TB: Maybe right answer is the summit at the tech plenary
PC: That may not happen.
TB: This is pressing. People want multiend links and are hacking horribly to do this.
NW: When XLink was done, it was made a little too general.
TB: See my concrete proposal, with support from Ann Navarro
[Scribe stops minuting since discussion and scribe a bit unfocused]
PC Summarizing some options for moving forward:
  1. We listen to the AC tomorrow and Weds
  2. Work on a charter, and send to AC for discussion.
  3. Wait for special meeting in March (if it happens). But several people think this is too late.
NW: I think we should do this sooner rather than later. We should convene interested parties before Mar 2003.
DC: We could invite people to our Feb ftf meeting to discuss this.
[Chris]
html, smil, xforms, svg
Action SW: Create such a special-interest telcon

The following people committed to attending such as meeting: TB, CL, NW.

DC: people who are the right hot people should be there. Docbook folks, too. Client builders (e.g., Tantek Celik and others). Ask for attendance by way of the HMTL Coordination Group and the XML Coordination Group.

2.5 Postponed

  1. contentPresentation-26
    1. Action CL 2002/09/24: Draft text on the principle of separation of content and presentation for the Arch Doc.
  2. rdfmsQnameUriMapping-6
    1. The Schema WG is making progress; they will get back to us when they're done. See XML Schema thread on this topic.
  3. uriMediaType-9:
  4. Status of discussions with WSA WG about SOAP/WSDL/GET/Query strings?

Ian Jacobs, for TimBL
Last modified: $Date: 2007/01/11 14:36:56 $