- From: Norman Walsh <ndw@nwalsh.com>
- Date: Mon, 27 Aug 2007 11:55:39 -0400
- To: public-xml-processing-model-wg@w3.org
- Message-ID: <m2y7fxas5g.fsf@nwalsh.com>
/ ht@inf.ed.ac.uk (Henry S. Thompson) was heard to say: | Today's discussion has raised the, for me at least, deep question of | just what the types we have been semi-formally associating with step | options really mean. One way of framing this was suggested by Norm: | | Are | <p:option name='attribute-name' value='x:foo'>...</p:option> | and | <p:option name='attribute-name' select="'x:foo'">...</p:option> | | indistinguishable, regardless of what, if anything, replaces the | ellipses? I think they should be. | I guess I can live with this, but the spec. has to change to make | clear that what is now described as the in-scope namespaces of the | XPath dynamic context is available for _all_ option evaluation, and | specify what namespace bindings are available for parameter | evaluation. Also, the fact that the prefixes in what we call QNames | are interpreted relative to the in-scope namespaces as we define it | needs to be made clear. I'm concerned about the impact of this on the | spec. from the perspective of the 99%-case user, who only uses 'value' | to set options and parameters, and wants to think of QName values as | just-like-element-name QNames. I don't think the 99% case will ever use p:namespaces, so I don't see ordinary users ever having any trouble with it. | OK, so having got that off my chest, where does this leave us with | respect to a coherent proposal for adding type information to at least | options? | | I propose that we add a 'type' attribute to p:option and p:parameter, | and a 'type-prefixes' attribute to p:pipeline and p:pipeline-library, | syntax and semantics as follows: | | type-prefixes -- a whitespace-delimited list of prefixes, all of | which *must* have in-scope namespace declarations on the spot. | | type -- A QName per XML Namespaces 1.1, which *must* have a prefix, | which *must* be in an ancestor's type-prefixes. Interpreted to | produce a URI by concatenating the binding of the type prefix, a '#' | if it doesn't end with one already, and the local-name part. This | URI identifies a type definition. | | Implementations *must* recognise and enforce the the types used in | section 7.1 below, namely xs:anyURI, xs:boolean, xs:integer, p:QName, | p:XPath-expression and p:XSLT-match-pattern, in their occurrences on Adding our own type definitions just seems totally over-the-top to me. And the fact that we'd have to to make a useful proposal is one of the things that convinces me we shouldn't do this until V.next. If ever. Be seeing you, norm -- Norman Walsh <ndw@nwalsh.com> | Whoever is abandoned by hope has also http://nwalsh.com/ | been abandoned by fear; this is the | meaning of the word "desperate."-- | Schopenhauer
Received on Monday, 27 August 2007 15:55:49 UTC