W3C

RDF in XHTML Task Force

19 Mar 2009

Agenda

See also: IRC log, previous 2009-03-05

Attendees

Present
Ralph Swick, Mark Birbeck, Shane McCarron, Manu Sporny, Steven Pemberton, Ben Adida
Regrets
Michael Hausenblas
Chair
Ben
Scribe
Ralph

Contents


 

<ShaneM> CURIE Javascript: http://www.w3.org/MarkUp/xhtml2/wiki/CurieJavascript

Shane: I had an action for generating CURIEs

Action Review

ACTION: [DONE] Manu to clean up TC 9001, 9002, 9003. [recorded in http://www.w3.org/2009/03/05-rdfa-minutes.html#action13]

Manu: 9001 through 9004 now use identical markup except for how the prefix is defined

ACTION: [DONE] Manu to create TC for space-separated syntax for @prefix. [recorded in http://www.w3.org/2009/03/05-rdfa-minutes.html#action14]

Manu: that's test 9004

ACTION: [PENDING] Ben to put up information on "how to write RDFa" with screencast possibly and instructions on bookmarklet. [recorded in http://www.w3.org/2008/11/06-rdfa-minutes.html#action12]

ACTION: [PENDING] Jeremy to demonstrate GRDDL with XHTML/RDFa once the NS URI is set up. [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action03]

ACTION: [PENDING] Manu to look at http://lists.w3.org/Archives/Public/public-rdf-in-xhtml-tf/2008Dec/0037.html about resolving relative URIs [recorded in http://www.w3.org/2009/01/08-rdfa-minutes.html#action15]

Manu: this was a request to add a note to the document that if Saxon or RFC2396 is used for relative URI resolution you won't get the correct result
... I sent a note but want the TF to consider whether this is the right approach
... the tests in question are already negative tests, which the original mail didn't realize
... RFC3986 replaces RFC2396
... it appears the URL that is generated in the corner case is different
... affects test 114
... attribution URL should be to the W3C Web site

<benadida> content is href="../../../../../../../../../../"

Manu: the author of Saxon has said he intends to move to RFC3986 but that Saxon currently still follows RFC2396
... my proposal is just to document that RDFa follows RFC3986
... adding this note to test case 114 would resolve this issue, I believe
... add the note in the SPARQL result

Ben: sounds good

ACTION: [PENDING] Manu to write summary for Semantic Web Use Cases for Ivan. [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action09]

ACTION: [PENDING] Mark create base wizard suitable for cloning [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action12]

ACTION: [PENDING] Mark to review reasoning on setting explicit about="" on HEAD and BODY [recorded in http://www.w3.org/2008/12/18-rdfa-irc]

ACTION: [PENDING] Mark to send Ben ubiquity related wizard stuff [recorded in http://www.w3.org/2008/11/20-rdfa-minutes.html#action11]

ACTION: [PENDING] Mark write foaf examples for wiki [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action13]

ACTION: [PENDING] Michael to create 'RDFa for uF users' on RDFa Wiki [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action14]

ACTION: [PENDING] Ralph or Steven fix the .htaccess for the XHTML namespace [recorded in http://www.w3.org/2009/01/08-rdfa-minutes.html#action01]

ACTION: [PENDING] Ralph think about RSS+RDFa [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action15]

Primer Aside

Ben: I think the simplification of the Primer was the right choice at the time
... but now I think it's falling short of what's needed
... wonder about adding some more advanced material back in

Manu: I fear that the size of the document would put people off
... so a separate Advanced Primer would be better

Ben: Primer can be updated with a reference to a [new] Advanced Primer
... we're getting some interesting screen casts
... e.g. the Drupal one
... I'd like to see a screen cast on "here's how to add your RDFa markup and here's how to test that you did it correctly"

<Steven> Go Ben!

<markbirbeck> mark-birbeck/blog/2009/01/rdfa-means-extensibility

Test Cases

<msporny> rdfa-test-harness

Manu: my highest priority is to decide on the syntax for @prefix value
... see design test suite / unapproved
... there are tests for 4 different syntaxes
... we should pick one

Ben: let's try a quick poll, ok?

<markbirbeck> I'm afraid I have a 5th....

<ShaneM> note that in test 9003 the syntax of some prefixes seems wrong

Ben: in the colon syntax sometimes there's whitespace following the colon and sometimes not

Manu: intentionally so to generate discussion

Ben: so, let's try polling first with no 'extra' whitespace

<markbirbeck> I forgot that I thought of this the other day...but what about JSON syntax? Radical, I know, but makes for some interesting things.

<markbirbeck> e.g.:

<markbirbeck> prefix="xsd: http://www.w3.org/2001/XMLSchema#, dcterms:http://purl.org/dc/terms/, media: http://purl.org/media#, audio:http://purl.org/media/audio#"

<markbirbeck> Note the commas.

<markbirbeck> But also allowed would be:

Ben: 9002 uses colon and semicolon

<ShaneM> ShaneM prefers prefix="PREFIX=URI PREFIX2=URI2"

<markbirbeck> prefix="'xsd': 'http://www.w3.org/2001/XMLSchema#', 'dcterms':'http://purl.org/dc/terms/', 'media': 'http://purl.org/media#', 'audio':'http://purl.org/media/audio#'"

<markbirbeck> Note the quotes.

Ben: 9001 uses colon and whitespace

option 1 - from 9001: prefix="xsd: http://www.w3.org/2001/XMLSchema# dcterms:http://purl.org/dc/terms/ media: http://purl.org/media# audio:http://purl.org/media/audio#"

option 2 - from 9002: prefix="xsd: http://www.w3.org/2001/XMLSchema#; dcterms:http://purl.org/dc/terms/; media: http://purl.org/media# ; audio: http://purl.org/media/audio#;"

option 3 - from 9003: prefix="xsd=http://www.w3.org/2001/XMLSchema# dcterms = http://purl.org/dc/terms/ media=http://purl.org/media# audio = http://purl.org/media/audio#"

option 4 - from 9004: prefix="xsd http://www.w3.org/2001/XMLSchema# dcterms http://purl.org/dc/terms/ media http://purl.org/media# audio http://purl.org/media/audio#"

<msporny> I think focusing on simplicity buys us a great deal here, Mark - which is why I'd like to stay away from CSS-like and JSON-like syntax.

<msporny> HTML5 folks would be all over the "complex syntax" that we've chosen

<markbirbeck> I disagree.

<markbirbeck> Having a breaking character between pairs is not complex!

Ralph: I think 9004 would generate objections w.r.t. future extensibility

<ShaneM> markbirbeck: not between pairs - having the same character as a delimiter and a spacing character is the confusion point I think.

Mark: the alternating list ala 9005 is bad
... as is a syntax that doesn't delimit pairs
... we shouldn't try to be simple when authors use more complex syntaxes every day
... I was warming to a CSS-like syntax but then it occurred to me that a lot of people are familiar with JSON format

Ben: nested quotes ala the JSON notation bothers me

Mark: that was the second alternative
... first JSON-like alternative doesn't have nested quotes but does use comma to separate the pairs

<benadida> rel="dc:license cc:license"

Ben: for teaching this to folks, we're already seeing space-separated properties in @rel
... for groking a syntax, I like similarity [with @rel]
... e.g. 9001
... though I think the extra spaces [in 9001] would confuse things

<markbirbeck> xsd:h...

Ben: 9001 mixes in some extra spaces

Mark: so prefix:value SPACE prefix:value ... ?

Ben: yes

<Steven> I like the use of "="

Mark: this looks too much like URLs

<Steven> because it reads like it is

Mark: I can live with 9002
... in 9003 I'd want to disallow the spaces around '='

Ben: yes, we're thinking of space as a separator

<benadida> med:ia/image

Ben: so no space around '='

Mark: I don't see a point in throwing errors when there's extra space, e.g., around '='
... the syntax should be forgiving

Ben: let's get a feeling for where we stand now

Mark: include comma-separated colon pairs

<benadida> Option 5: Mark's JSON-like

Manu: a=b and a = b are both perfectly parseable without additional separate between the pairs
... the additional comma or semicolon definitively separates the pairs

Steven: both comma and semicolon can be part of URLs

<Steven> http://www.w3.org/2001/XMLSchema#;

<Steven> is a valid URL

Ben: poll is not a commitment

<msporny> +1 for prefix="a <SEPARATOR> b <PAIR_SEPARATOR> x <SEPARATOR> y"

Ralph: prefer option 3 '='

<ShaneM> More importantly... http://www.w3.org/2001/XMLSchema?asd,abc;def is also a legal url

Manu: prefer any option that has a separator and a pair separator

Manu: so I'd be ok with 5 (and 2)

Shane: prefer option 3

Steven: prefer option 3

Ben: prefer 1, can live with 3

Mark: prefer 5, can live with 2
... can't live with 3

Manu: can't live with 3; saying space is disallowed is harsh

Ben: could allow space around the '='

Manu: but '=' can appear in URLs

Shane: '=' in URLs wouldn't break parsing

Mark: I see no need to create another syntax within values

<markbirbeck> x="y=z"

Mark: and '=' is so familiar for setting the attribute value that I think we're asking for trouble using it inside values

<ShaneM> x="Y:Z"

Ben: that seems to argue for option 1
... it would also be quite new to use JSON syntax inside an attribute value

Shane: the alternating list pattern is use in xml:schemaLocation

Ben: yep, I remember that pattern there -- and when the list gets long it becomes very confusing
... so I count that as an existing bad pattern

Manu: worth floating this to mail?

<markbirbeck> +1 to Ben

Ben: mail on the rdfa TF list ok
... next meeting in 2 weeks; on 2 April

Summary of Action Items

[PENDING] ACTION: Ben to put up information on "how to write RDFa" with screencast possibly and instructions on bookmarklet. [recorded in http://www.w3.org/2008/11/06-rdfa-minutes.html#action12]
[PENDING] ACTION: Jeremy to demonstrate GRDDL with XHTML/RDFa once the NS URI is set up. [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action03]
[PENDING] ACTION: Manu to look at http://lists.w3.org/Archives/Public/public-rdf-in-xhtml-tf/2008Dec/0037.html about resolving relative URIs [recorded in http://www.w3.org/2009/01/08-rdfa-minutes.html#action15]
[PENDING] ACTION: Manu to write summary for Semantic Web Use Cases for Ivan. [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action09]
[PENDING] ACTION: Mark create base wizard suitable for cloning [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action12]
[PENDING] ACTION: Mark to review reasoning on setting explicit about="" on HEAD and BODY [recorded in http://www.w3.org/2008/12/18-rdfa-irc]
[PENDING] ACTION: Mark to send Ben ubiquity related wizard stuff [recorded in http://www.w3.org/2008/11/20-rdfa-minutes.html#action11]
[PENDING] ACTION: Mark write foaf examples for wiki [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action13]
[PENDING] ACTION: Michael to create 'RDFa for uF users' on RDFa Wiki [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action14]
[PENDING] ACTION: Ralph or Steven fix the .htaccess for the XHTML namespace [recorded in http://www.w3.org/2009/01/08-rdfa-minutes.html#action01]
[PENDING] ACTION: Ralph think about RSS+RDFa [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action15]
 
[DONE] ACTION: Manu to clean up TC 9001, 9002, 9003. [recorded in http://www.w3.org/2009/03/05-rdfa-minutes.html#action13]
[DONE] ACTION: Manu to create TC for space-separated syntax for @prefix. [recorded in http://www.w3.org/2009/03/05-rdfa-minutes.html#action14]
 
[End of minutes]

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$Date: 2009/03/19 16:28:34 $