14:51:00 <RRSAgent> RRSAgent has joined #rdfa
14:51:00 <RRSAgent> logging to http://www.w3.org/2009/04/02-rdfa-irc
14:51:07 <Ralph> Meeting: RDF-in-XHTML Task Force
14:51:15 <Ralph> agenda: http://lists.w3.org/Archives/Public/public-rdf-in-xhtml-tf/2009Apr/0018.html
14:51:45 <Ralph> -> http://www.w3.org/2009/03/19-rdfa-minutes.html previous 2009-03-19
14:52:15 <Ralph> regrets+ Michael
14:52:34 <Ralph> regrets+ Ben_Adida
14:52:38 <Ralph> regrets+ Michael_Hausenblas
14:52:49 <Ralph> regrets- Michael
14:53:06 <Ralph> rrsagent, please make record public
15:01:19 <Zakim> SW_SWD(RDFa)11:00AM has now started
15:01:26 <Zakim> +Ralph
15:01:46 <markbirbeck> markbirbeck has joined #rdfa
15:02:14 <Zakim> +??P27
15:02:25 <msporny> zakim, I am ??P27
15:02:36 <Zakim> +msporny; got it
15:04:32 <ShaneM> ShaneM has joined #rdfa
15:04:43 <ShaneM> laptop has gone deeply insane - wokring on it
15:05:49 <Zakim> +ShaneM
15:06:31 <Ralph> chair: Manu
15:06:34 <msporny> http://www.w3.org/2009/03/19-rdfa-minutes.html
15:06:51 <Ralph> [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]
15:06:57 <Ralph> [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]
15:07:46 <Ralph> 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]
15:07:54 <Ralph> Manu: I've replied and asked twice for a response
15:08:11 <Ralph> ... I think they're accepting the response
15:08:16 <Ralph> ... so I think we can consider this done
15:08:20 <Ralph> --done
15:08:26 <Ralph> [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]
15:08:39 <Ralph> ACTION: Mark create base wizard suitable for cloning [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action12]
15:08:53 <msporny> Mark, are you going to dial in soon? We're at your action items...
15:09:13 <Ralph> i|http://www.w3.org/2009/03/19-rdfa-minutes.html|Topic: Action Review
15:09:21 <markbirbeck> I'm about to dial in.
15:09:29 <markbirbeck> However, I have no updates on my actions.
15:09:31 <RRSAgent> I have made the request to generate http://www.w3.org/2009/04/02-rdfa-minutes.html Ralph
15:09:32 <Ralph> -- continues
15:09:44 <Ralph> [DONE] ACTION: Mark to review reasoning on setting explicit about="" on HEAD and BODY [recorded in http://www.w3.org/2008/12/18-rdfa-irc]
15:09:54 <markbirbeck> Oh...other than that one. :)
15:10:15 <Ralph> -> http://lists.w3.org/Archives/Public/public-rdf-in-xhtml-tf/2009Apr/0000.html The implied @about="": Explanation and some problems [Mark Birbeck  2009-04-01]
15:10:22 <Ralph> [PENDING] ACTION: Mark to send Ben ubiquity related wizard stuff [recorded in http://www.w3.org/2008/11/20-rdfa-minutes.html#action11]
15:10:25 <markbirbeck> zakim, code?
15:10:25 <Zakim> the conference code is 7332 (tel:+1.617.761.6200 tel:+33.4.89.06.34.99 tel:+44.117.370.6152), markbirbeck
15:10:26 <Ralph> [PENDING] ACTION: Mark write foaf examples for wiki [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action13]
15:10:32 <Ralph> [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]
15:10:43 <Ralph> ACTION: Ralph or Steven fix the .htaccess for the XHTML namespace [recorded in http://www.w3.org/2009/01/08-rdfa-minutes.html#action01]
15:11:02 <Zakim> +??P4
15:11:04 <Ralph> Ralph: I know Steven poked someone about this
15:11:08 <markbirbeck> zakim, i am ?
15:11:08 <Zakim> +markbirbeck; got it
15:11:09 <Ralph> -- continues
15:11:13 <Ralph> [PENDING] ACTION: Ralph think about RSS+RDFa [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action15]
15:12:36 <Ralph> Topic: Report on AC Meeting
15:12:54 <Ralph> Manu: anyone there for the HTML discussions than Ben and Steven?
15:13:04 <Ralph> Shane: unfortunately Ben couldn't stay for the breakout session
15:13:18 <Ralph> Mark: the minutes suggest the discussion was quite positive
15:14:02 <Ralph> Ralph: I needed to participate in a different breakout
15:14:14 <Ralph> Mark: I'm looking at the minutes of the Backplane XG
15:15:39 <Ralph> Shane: there appears to be substantial support from the Membership for the extensibility model that XHTML has always had
15:16:45 <Ralph> Topic: @prefix syntax discussion
15:17:10 <Ralph> Manu: at our last discussion, Shane and Ralph were favoring the '=' syntax and Mark and I were favoring the JSON-esque syntax
15:17:29 <Ralph> ... any new thoughts in the subsequent 2 weeks?
15:18:16 <Ralph> Mark: I'm involved in a couple of projects where folk are producing what they think is RDFa
15:19:09 <Ralph> ... it's interesting; I see a growing need for tools to check the work
15:19:18 <Zakim> -ShaneM
15:20:28 <Ralph> ... simply typos like mismatch between namespace declaration and usage
15:20:48 <Zakim> +??P0
15:20:50 <ShaneM> ShaneM has joined #rdfa
15:21:51 <Ralph> Ralph: no real additional thoughts but I did make note of Mark's concerns about the pattern @attr="prefix=value"
15:22:03 <Ralph> ... but if tools are generating this anyway, how much does it matter?
15:22:16 <Ralph> Mark: I'm thinking of checking tools more than generation tools
15:22:39 <Ralph> Manu: definitely think embedded '=' will cause confusion
15:22:55 <Ralph> ... and people will put whitespace around the '='
15:23:05 <Ralph> ... so we need resilient syntaxes and parsers
15:23:36 <Ralph> Shane: I don't think it's terribly important to have delimiters other than whitespace between the items
15:23:45 <Ralph> ... but I won't fight on that
15:23:56 <Ralph> ... I understand the sensitivity to the repeated '=' issue
15:24:00 <Ralph> ... do you prefer ':'?
15:24:01 <Ralph> Manu: yes
15:24:17 <Ralph> Shane: that's probably fine, but then you end up with repeated ':'
15:24:26 <ShaneM> perfix="xhv:http:..."
15:25:03 <Ralph> Shane: I leaned toward repeated '=' in the first place because that made it clear which was the prefix and which was the rest
15:25:07 <markbirbeck> prefix="xhv:xyz dc:xyz"
15:25:13 <markbirbeck> prefix="xhv=xyz dc=xyz"
15:25:25 <Ralph> Mark: we're tending to discuss as if ^ were the patterns
15:25:43 <Ralph> ... this is how @xml:schemalocation works
15:25:44 <markbirbeck> prefix="
15:25:45 <markbirbeck>   xhv: xyz,
15:25:45 <markbirbeck>   dc: xyz
15:25:45 <markbirbeck> "
15:26:02 <Ralph> Mark: I'm thinking we should really be looking at layout such as ^
15:26:16 <Ralph> ... in this case, additional delimiters are useful; we don't need to be compact
15:26:37 <Ralph> ... we should consider not just a syntax but also examples that people will cut & paste
15:27:15 <Ralph> ... if I were to copy one of Manu's audio prefix examples I could select a single line (of many declarations) and insert it into my list without introducing error
15:27:26 <Ralph> ... once you spread things out like this, why not allow further flexibility
15:27:27 <markbirbeck> prefix="
15:27:27 <markbirbeck>   "xhv": 'xy    z',
15:27:27 <markbirbeck>   dc: xyz
15:27:28 <markbirbeck> "
15:27:42 <markbirbeck> prefix="
15:27:43 <markbirbeck>   'xhv': 'xy    z',
15:27:43 <markbirbeck>   dc: xyz
15:27:43 <markbirbeck> "
15:28:12 <Ralph> Shane: my concern is that URIs allow these characters, so the syntax rules and the parsing are both more challenging
15:28:24 <Ralph> Mark: yes, but there are extra options for delimiting
15:28:49 <Ralph> ... if we say we're allowing quotes _as well_ this gives additional flexibility
15:28:50 <markbirbeck> prefix="
15:28:50 <markbirbeck>   'xhv': 'xy    z,',
15:28:51 <markbirbeck>   dc: xyz
15:28:51 <markbirbeck> "
15:29:17 <Ralph> Mark: if you did have a URI that ends in ',' then quoting allows an easy way to include it
15:29:45 <Ralph> ... ':' in @xmlns was really an effort to find one thing that would work
15:30:00 <Ralph> ... but we have greater flexibility
15:30:24 <Ralph> Manu: when people mint prefix mapping URIs I find it highly unlikely that they'll use a ',' in such a URI
15:30:57 <Ralph> ... yes, it _could_ happen but if it's a well-known design consideration that such characters cause trouble then vocabulary developers can avoid them
15:30:57 <ShaneM> q+ to talk about embedding commas
15:31:05 <Ralph> Mark: what is the added complexity?
15:31:21 <Ralph> Manu: it's additional complexity in the parser.  I'm questioning whether we really need it.
15:31:28 <Ralph> Mark: it's one regular expression
15:31:51 <Ralph> ... a way of trying to introduce resilience and something that [humans] can grok easily
15:32:09 <Ralph> ... we come back to this problem of recognizing what is a URI
15:32:36 <Ralph> ... I'm just thinking of ways to provide resilience when needed without mandating it all the time
15:32:44 <markbirbeck> prefix="
15:32:45 <markbirbeck>   xhv: {xy    z,},
15:32:45 <markbirbeck>   dc: xyz
15:32:45 <markbirbeck> "
15:33:04 <Ralph> Manu: I'd like to see the regex
15:33:32 <Ralph> ... my C+sax-based parser doesn't have to use regex's anywhere right now
15:33:46 <Ralph> Mark: a space-separated list needs to be cracked into a list
15:33:54 <Ralph> ... even '=' can appear in a URI
15:33:55 <ShaneM> index
15:34:06 <Ralph> index()
15:34:07 <Ralph> :)
15:34:28 <Ralph> Manu: I don't think we can count on authors writing examples consistently
15:34:39 <Ralph> ... and a mixture of styles will cause confusion
15:35:00 <Ralph> Mark: I'm proposing the _possibility_ of permitting this richer format, not _requiring_ it
15:35:46 <Ralph> Manu: I was only questioning whether example authors will really write the examples with multi-line declarations
15:35:52 <markbirbeck> prefix="xhv: xy, dc: xyz"
15:36:08 <Ralph> ... when the examples are written on a single line the richer syntax becomes confusing
15:36:29 <Ralph> Mark: consider space-separated lists
15:36:30 <markbirbeck> prefix="xhv:xy dc:xyz"
15:36:41 <Ralph> ... then you can't have space around ':'
15:36:53 <Ralph> ... the options for authors laying out the markup are limited
15:37:31 <Ralph> ... no flexibility for aligning things [in columns]
15:38:12 <Ralph> ... whereas the XML attribute syntax has a lot of flexibility, for example; can use whitespace to nudge things [into columns]
15:38:40 <Ralph> ... in terms of consistency, generally in XML spaces are ignored
15:39:03 <Ralph> ... other than the use in XML Schema to create lists, whitespace is not significant
15:39:20 <Ralph> Shane: whitespace is collapsed, not ignored
15:39:25 <Ralph> ... this includes newlines
15:39:37 <Ralph> ... collapsing inside attributes values
15:39:49 <Ralph> ... however, this is bad; in the HTML DOM whitespace is not collapsed
15:40:12 <Ralph> ... this means a parser that has to work with both XML and HTML has to be written to expect multiple whitespace
15:40:34 <Ralph> Mark; but the presence of whitespace is geenerally not significant
15:40:39 <Ralph> s/;/:
15:40:53 <Ralph> ... as long as there is whitespace in key places, such as between attributes
15:41:13 <Ralph> ... '=' vs. ':' is a separate discussion from whether whitespace is a delimiter
15:41:28 <Ralph> Manu: I agree; we shouldn't decide solely on whitespace
15:41:41 <msporny> prefix="xhv:xy, dc:xyz"  prefix="xhv:xy; dc:xyz"
15:41:55 <Ralph> ... for delimiters between mappings, we're considering something like ^
15:42:17 <Ralph> Shane: a lot of our canonical examples are ones that contain ','; e.g. Wikipedia or Amazon
15:42:29 <Ralph> ... places where, for example, an ISBN might be interpolated
15:42:45 <msporny> prefix="media: http://purl.org/media#, audio: http://purl.org/media/audio#"
15:42:53 <Ralph> Mark: yeah, can't quickly come up with an example
15:43:02 <markbirbeck> mapping, mapping, mapping
15:43:12 <Ralph> Mark: should treat as ^
15:43:22 <Ralph> ... then decide what goes inside 'mapping'
15:43:32 <msporny> prefix="media: http://purl.org/media# ; audio : http://purl.org/media/audio#"
15:43:41 <Ralph> Shane: can't just be 'ends in ,' -- must be 'includes ,'
15:44:18 <Ralph> Manu: are Shane and Ralph ok with using ',' between mappings?
15:44:30 <Ralph> Shane: if we're going to use ',' or ';' we need to define the escaping mechanism
15:44:41 <Ralph> ... maybe there's already a mechanism defined somewhere
15:45:01 <Ralph> ... my preferred syntax is identical to schemalocation but Ralph says that's a non-starter
15:45:15 <Ralph> Manu: ok to pick a character that must be URI-encoded in URIs?
15:45:37 <msporny> http://en.wikipedia.org/wiki/Percent-encoding
15:45:42 <Ralph> Mark: every time I look at the URI spec I find it allows more characters than I expected
15:46:08 <Ralph> ... this discussion is pretty much the same discussion the @xmlns folk had to go through
15:47:07 <Ralph> Manu: we could require that reserved characters must be %-encoded
15:47:18 <Ralph> ... but that makes everything harder
15:47:27 <Ralph> Mark: and we'd have to avoid a requirement to double-encode
15:47:36 <Ralph> ... we need a non-reserved character
15:47:39 <Ralph> Shane: good luck with that!
15:47:48 <Ralph> ... remember that in the case of CURIE it's a IRI
15:47:57 <Ralph> ... so even a bigger set of non-reserved character
15:48:14 <Ralph> ... the only reserved character is space
15:48:37 <Ralph> ... even schemalocation cheated by not using '=' or ':'; they just use alternation
15:48:56 <Ralph> ... the problem with alternation is that we can't do anything clever with default or absent prefixes
15:49:12 <Ralph> ... but maybe we don't need such rules
15:49:29 <msporny> prefix="a=b x=y"
15:50:39 <ShaneM> wow.... we already have this problem!
15:50:42 <Ralph> Mark: if we needed @prefix on every element then perhaps we might go with [the '=' syntax]
15:50:52 <ShaneM> xmlns:foo="URI"    what happens if URI contains a quotation mark?
15:50:53 <Ralph> ... but perhaps we don't need that flexibility; be more restrictive
15:51:16 <Ralph> ... put everything in the head or having a predicate indicating a prefix mapping
15:51:31 <Ralph> Ralhp: predicate as in RDF predicate?
15:51:33 <Ralph> Mark: yes
15:51:41 <ShaneM> <meta rel="prefix" name="foo" resource="URI" />
15:51:57 <Ralph> ... however I didn't like that syntax as it puts meta information in the same graph as 'ordinary' information, which feels wrong
15:52:22 <Ralph> ... I'm looking for something that is "cut-and-paste reliable"
15:53:05 <Ralph> Ralph: Creative Commons would not accept restrictions on where mappings can be declared
15:53:57 <Ralph> Shane: separate two issues; 1. can we provide an alternative to @xmlns that would be acceptable beyond the XML community and 2. how do we make it easier for our constituents to use RDFa in ways @@
15:54:36 <Ralph> s/ways @@/easier ways
15:54:49 <Ralph> ... we've talked about having external documents that declare prefixes
15:55:13 <Ralph> ... perhaps even with some well-known prefix declarations
15:55:34 <Ralph> ... maybe we'll make more progress by not trying to find a single solution to these two objectives
15:55:44 <Ralph> Mark: so do we need a lot of flexibility?
15:55:55 <Ralph> ... find just enough flexibility for the goals at hand
15:56:12 <ShaneM> We should try hard to NOT over-engineer this solution without having the requirements in mind!
15:56:17 <Ralph> Manu: the second idea is that there's an @profile value that pulls in external mapping declarations
15:56:48 <Ralph> Mark: 1 is the namespace thing and 2 is ease of authoring
15:57:35 <Ralph> Shane: consider CSS syntax as an example of going too far; e.g. borders on table cells -- totally different behavior depending on how many values are supplied
15:57:45 <markbirbeck> dc: url(xyz)
15:57:49 <Ralph> Mark: I've just thought of another syntax!
15:58:43 <Ralph> Ralph: and it may be that the @xmlns problem will go away
15:58:55 <markbirbeck> Continuing Shane's point, why not 'solve' this:
15:58:57 <markbirbeck> http://wiki.creativecommons.org/CcREL
16:00:19 <Ralph> Mark: pick an example of something people will frequently want to copy and paste; e.g. ccRel
16:00:30 <Ralph> ... the simple example [in ccRel] is interesting
16:00:51 <Ralph> ... it just says some other mechanism has defined the token
16:01:41 <Ralph> ... consider the lengthier scenarios; what other ways are there to address these?
16:01:57 <Ralph> Manu: any of our proposed syntaxes would handle these examples fairly cleanly
16:02:22 <msporny> prefix="a = b x = y"
16:02:24 <Ralph> Ralph: yeah, it's the ugly corner cases like ',' in URIs that are a problem
16:02:29 <msporny> prefix="a=b x=y"
16:02:35 <Ralph> Shane: even quote is already an issue
16:02:55 <Ralph> Manu: a simple state machine will handle the '=' syntax
16:03:22 <ShaneM> prefix="
16:03:22 <ShaneM>      a = b
16:03:22 <ShaneM>      x = y
16:03:22 <ShaneM> "
16:03:23 <Ralph> ... I see the argument for an extensible syntax that could support every use case but I wonder if [that flexiblity] will ever be used
16:03:38 <Ralph> ... we're trying to solve a very simple problem
16:04:01 <Ralph> Shane: Mark's desire to make this legible can easily be written using the '=' syntax
16:04:07 <markbirbeck> Shane don't we do this: xmlns:a="&quot;b&quot;"
16:04:08 <Ralph> ... we can easily deal with extra whitespace
16:04:28 <markbirbeck> a = http://example.org?a=b
16:04:46 <ShaneM> (.*")\s*=\s*(.*?)\s+
16:05:05 <markbirbeck> prefix="a = http://example.org?a=b&c=d"
16:07:11 <Ralph> Manu: I'm leaning toward preferring this solution
16:07:17 <Ralph> ... straightforward and easy to implement
16:07:25 <ShaneM> actually - can't use \s... need [\s\r\n]
16:07:32 <Ralph> ... don't think there's much danger of authors confusing the syntax in the markup
16:08:05 <Zakim> -msporny
16:08:06 <Zakim> -markbirbeck
16:08:09 <Ralph> next meeting: 2 weeks (April 16)
16:08:11 <Ralph> [adjourned]
16:08:21 <ShaneM> (.*)[\s\r\n]*=[\s\r\n]*(.*?)[\s\r\n]+
16:08:25 <Ralph> rrsagent, please draft minutes
16:08:25 <RRSAgent> I have made the request to generate http://www.w3.org/2009/04/02-rdfa-minutes.html Ralph
16:10:08 <Zakim> -Ralph
16:10:10 <Zakim> -??P0
16:10:11 <Zakim> SW_SWD(RDFa)11:00AM has ended
16:10:13 <Zakim> Attendees were Ralph, msporny, ShaneM, markbirbeck
16:10:26 <Ralph> rrsagent, please draft minutes
16:10:26 <RRSAgent> I have made the request to generate http://www.w3.org/2009/04/02-rdfa-minutes.html Ralph
16:14:21 <Ralph> zakim, bye
16:14:21 <Zakim> Zakim has left #rdfa
16:14:23 <Ralph> rrsagent, bye
16:14:23 <RRSAgent> I see 3 open action items saved in http://www.w3.org/2009/04/02-rdfa-actions.rdf :
16:14:23 <RRSAgent> 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] [1]
16:14:23 <RRSAgent>   recorded in http://www.w3.org/2009/04/02-rdfa-irc#T15-07-46
16:14:23 <RRSAgent> ACTION: Mark create base wizard suitable for cloning [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action12] [2]
16:14:23 <RRSAgent>   recorded in http://www.w3.org/2009/04/02-rdfa-irc#T15-08-39
16:14:23 <RRSAgent> ACTION: Ralph or Steven fix the .htaccess for the XHTML namespace [recorded in http://www.w3.org/2009/01/08-rdfa-minutes.html#action01] [3]
16:14:23 <RRSAgent>   recorded in http://www.w3.org/2009/04/02-rdfa-irc#T15-10-43