- From: Norman Walsh <ndw@nwalsh.com>
- Date: Wed, 04 Feb 2015 10:02:08 -0600
- To: public-xml-processing-model-wg@w3.org
- Message-ID: <87k2zxoebj.fsf@nwalsh.com>
See http://www.w3.org/XML/XProc/2015/02/04-minutes
[1]W3C
- DRAFT -
XML Processing Model WG
Meeting 264, 04 Feb 2015
[2]Agenda
See also: [3]IRC log
Attendees
Present
Loren, Norm, Jim, Henry
Regrets
Alex
Chair
Norm
Scribe
Norm
Contents
* [4]Topics
1. [5]Accept this agenda?
2. [6]Accept minutes from the previous meeting?
3. [7]Next meeting
4. [8]Do we need p:import-schema
5. [9]Should we adopt shadow attributes?
6. [10]Any other business?
* [11]Summary of Action Items
--------------------------------------------------------------------------
Accept this agenda?
-> [12]http://www.w3.org/XML/XProc/2015/02/04-agenda
Accepted.
Accept minutes from the previous meeting?
-> [13]http://www.w3.org/XML/XProc/2015/01/28-minutes
Accepted.
Next meeting
I propose 25 Feb for our next telcon.
No regrets heard.
Do we need p:import-schema
-> [14]https://github.com/xproc/specification/issues/92
Norm sets the stage...
Loren: It would be nice to have, but it could be very hard to implement.
Norm: I think we'd have to make it optional.
Henry: I think it would be good if we could do this in a way that operates
by only forwarding the relevant information to the places that need it.
... I think it would be good if we didn't have to implement schema
processing to be an XProc 2.0 processor.
<ht> so that's select="..." as="...", not select="... as ..."
Norm: I think it only bites us where we have sequence types in "as="
attributes.
<ht> Right?
<ht> Yes
Henry, yes.
<p:variable name="hatsize" select="$param - 4" as="my:hatsize"/>
<p:variable name="hatsize" select="$param - 4" as="xs:integer"/>
Henry: What are our obligations under the latter? Is all that we have to
do with this is record it?
Norm: No, I believe we have to validate it.
<ht> <p:variable name="hatsize" select="($param - 4) as xs:integer"/>
<ht> if (@x castable as xs:date)
<xsl:variable name="fred" select="(4 - 2) as xs:integer"/>
Norm: That doesn't work "as" isn't allowed there.
<ht> "2003-02-28" cast as xs:date
<xsl:variable name="fred" select="(4-2)" as="xs:integer"/> is the same as
let $fred = (4-2) as xs:integer
Henry: Given that "cast as" does work, I'd like to explore the possibility
that we say not just in spec prose but that we define select=x as=y as "x
cast as y"
... Then import schema is just something that defines the static context
for XPath evaluation, it doesn't cost us anything.
<jfuller> same thing with constructor func
<jfuller> eg usa:zipcode("12345")
<jfuller> ("12345" cast as usa:zipcode?).
Henry: I don't know if constructor functions work for user-defined types.
Jim: It's equivalent to the cast as expression.
Henry: It also pushes the error handling off to the substrate, which is
just fine.
Norm: We should think about this. "as" and "cast as" aren't the same, so
we should know what the differences are.
Henry: It seems to me that we need import schema even if we don't use them
in as= attributes. We want users to be able to write usa:zipcode in their
XPath expressions.
<jfuller> [15]http://www.w3.org/TR/xpath-30/#id-schema-import-processing
<jfuller> seems to align with leaving it to the host language
Norm and Henry speculate about the Saxon API.
Henry: Quoting from XSLT 2.0 if the "as" attribute is supplied then the
value is converted to the required type.
Norm: So that is cast as.
Henry: That's on xsl:param, we need xsl:variable.
Should we adopt shadow attributes?
-> [16]https://github.com/xproc/specification/issues/78
Norm explains: [17]http://www.w3.org/TR/xslt-30/#shadow-attributes
Norm: The question of whether or not xsl:params are in scope is an
interesting one.
(Yes, top-level xsl:params are static.)
Henry: Not at the sub-pipeline level, p:libraries have to be compiled
separately.
... I remember distinctly trying to do that with the document type
attribute on the xslt:output statement. The fact that you can't compute
the doctype that you want your output to have is very annoying.
<ht> I guess I think that's a vnext.1 feature
Jim: I'm not so enthusiastic.
Norm: Sounds like there isn't enthusiasm. Shall we decline this issue?
<ht> I'd like to see how that works in practice for XSLT before committing
Jim: I don't think we need to drop it, but I think we should have some
more time to think about it.
Norm: Ok, I'll leave it open for now.
Any other business?
None heard.
Adjourned.
Summary of Action Items
[End of minutes]
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Minutes formatted by David Booth's [18]scribe.perl version 1.140 ([19]CVS
log)
$Date: 2015-02-04 16:01:17 $
References
1. http://www.w3.org/
2. http://www.w3.org/XML/XProc/2015/02/04-agenda
3. http://www.w3.org/2015/02/04-xproc-irc
4. http://www.w3.org/XML/XProc/2015/02/04-minutes#agenda
5. http://www.w3.org/XML/XProc/2015/02/04-minutes#item01
6. http://www.w3.org/XML/XProc/2015/02/04-minutes#item02
7. http://www.w3.org/XML/XProc/2015/02/04-minutes#item03
8. http://www.w3.org/XML/XProc/2015/02/04-minutes#item04
9. http://www.w3.org/XML/XProc/2015/02/04-minutes#item05
10. http://www.w3.org/XML/XProc/2015/02/04-minutes#item06
11. http://www.w3.org/XML/XProc/2015/02/04-minutes#ActionSummary
12. http://www.w3.org/XML/XProc/2015/02/04-agenda
13. http://www.w3.org/XML/XProc/2015/01/28-minutes
14. https://github.com/xproc/specification/issues/92
15. http://www.w3.org/TR/xpath-30/#id-schema-import-processing
16. https://github.com/xproc/specification/issues/78
17. http://www.w3.org/TR/xslt-30/#shadow-attributes
18. http://dev.w3.org/cvsweb/~checkout~/2002/scribe/scribedoc.htm
19. http://dev.w3.org/cvsweb/2002/scribe/
Received on Wednesday, 4 February 2015 16:02:43 UTC