- From: Michael Rys <mrys@microsoft.com>
- Date: Wed, 5 Mar 2003 12:15:18 -0800
- To: "Caroline Rioux" <crioux@decisionsoft.com>
- Cc: <public-qt-comments@w3.org>
I don't quite understand your question. If you do not import any schemata explicitly, then the prefix xf: is not defined, however the xs: prefix is per default assigned to the " http://www.w3.org/2001/XMLSchema" namespace. Best regards Michael > -----Original Message----- > From: Caroline Rioux [mailto:crioux@decisionsoft.com] > Sent: Wednesday, March 05, 2003 2:19 AM > To: Michael Rys > Cc: public-qt-comments@w3.org > Subject: RE: Namespace considerations > > Thank you very much for your reply, it clears up a lot. > > Just to be clear though (before I implement this ;-)), Jonathan > mentions below that the datatypes in the > "http://www.w3.org/2001/XMLSchema-datatypes" namespace are only available > if that schema is imported. > > In the XPath 2.0 spec, section 2.6.2.1.1 (Basic XPath) it states that: > > "In a Basic XPath implementation, the in-scope schema definitions consist > of a fixed set of 48 predefined type definitions. These include the 44 > built-in datatypes defined in [XML Schema], plus four additional types: > fn:yearMonthDuration, fn:dayTimeDuration, xs:anySimpleType, and > xs:anyType." > > Wouldn't that mean that in a basic XPath2 implementation, without > importing > the above schema, only the third example below is legal? > > <snip> > > > > for example, if I bind xf to "http://www.w3.org/2001/XMLSchema" and > > > xs to "http://www.w3.org/2001/XMLSchema-datatypes", then which of > these > > > (or all?) are legal? > > > > > > 'cast as xs:string(xs:decimal("15.5"))' > > > 'cast as xf:string(xs:decimal("15.5"))' > > > 'cast as xf:string(xf:decimal("15.5"))' > > Also, > > > > On a different note, I thought that xs was bound to > > > "http://www.w3.org/2001/XMLSchema" in the spec simply for convenience. > > > You seem to imply that it is a predefined prefix which is always bound > to > > > "http://www.w3.org/2001/XMLSchema". > > > > This is correct. > > [I assume you mean that Jonathan's implication was correct?] So does this > mean that this xs: binding takes precedence over any other xs: binding > done by a user in a document? > > Thanks very much for your help, > Caroline > > > On Tue, 4 Mar 2003, Michael Rys wrote: > > > My apologies that nobody seem to have answered. > > > > See below for my reply. > > > > Best regards > > Michael > > > > > -----Original Message----- > > > From: Caroline Rioux [mailto:crioux@decisionsoft.com] > > > Sent: Tuesday, March 04, 2003 7:19 AM > > > To: public-qt-comments@w3.org > > > Subject: Re: Namespace considerations > > > > > > > > > Hi, > > > > > > I posted the following a few weeks ago.. if anyone could a look at > > this, > > > that would be great, > > > > > > Caroline > > > > > > -- > > > Caroline Rioux, Software Engineer +44-1865-203192 > > > DecisionSoft Limited > > http://www.decisionsoft.com > > > XML Development and Services > > > > > > ---------- Forwarded message ---------- > > > Date: Wed, 19 Feb 2003 16:29:09 +0000 (GMT) > > > From: Caroline Rioux <crioux@decisionsoft.com> > > > To: Jonathan Robie <jonathan.robie@datadirect-technologies.com> > > > Cc: public-qt-comments@w3.org > > > Subject: Re: Namespace considerations > > > > > > Thanks for the quick reply, > > > > > > What I am unsure about though, is whether or not users of an XPath2 > > > implementation can invoke constructors within either namespace? > > > > > > for example, if I bind xf to "http://www.w3.org/2001/XMLSchema" and > > > xs to "http://www.w3.org/2001/XMLSchema-datatypes", then which of > > these > > > (or all?) are legal? > > > > > > 'cast as xs:string(xs:decimal("15.5"))' > > > 'cast as xf:string(xs:decimal("15.5"))' > > > 'cast as xf:string(xf:decimal("15.5"))' > > > > > [Michael Rys] All are legal since they construct strings :-). And even > > if you remove the 's the above expressions should be legal. > > > > However note that as Jonathan points out below, xs:decimal is not really > > the same type as xf:decimal, instead xs:decimal is considered a subtype > > of xf:decimal. > > > > > On a different note, I thought that xs was bound to > > > "http://www.w3.org/2001/XMLSchema" in the spec simply for convenience. > > > You seem to imply that it is a predefined prefix which is always bound > > to > > > "http://www.w3.org/2001/XMLSchema". > > > > This is correct. > > > > > Yet the F&O specs do use the > > > xs: prefix for constructors, which is defined to be in the > > > "http://www.w3.org/2001/XMLSchema-datatypes" namespace. > > > > [Michael Rys] This is a bug and should be fixed in the next version. > > Ashok, please take note. > > > > > Thanks again for your help, > > > Caroline > > > > [Michael Rys] Thanks for your comment. > > > > > > > > On Wed, 19 Feb 2003, Jonathan Robie wrote: > > > > > > > > > > > Hi Caroline, > > > > > > > > Good question! The short answer is that you can use > > > > ""http://www.w3.org/2001/XMLSchema-datatypes" only if you import > > that > > > > schema. Even though the same set of datatypes are available under > > either > > > > namespace, the datatypes in the two namespaces are not exactly > > > identical. > > > > If you go to the above URI, you can download the schema for > > datatypes, > > > and > > > > you will see that it looks like the following excerpt: > > > > > > > > <schema xmlns="http://www.w3.org/2001/XMLSchema" > > > > targetNamespace="http://www.w3.org/2001/XMLSchema- > > > datatypes" > > > > version="$Id: XMLSchema-datatypes.xsd,v 1.5 2001/03/16 > > > > 20:53:32 ht Exp $"> > > > > > > > > <simpleType name="string"> > > > > <restriction base="string"/> > > > > </simpleType> > > > > > > > > <simpleType name="boolean"> > > > > <restriction base="boolean"/> > > > > </simpleType> > > > > <!-- SNIP --> > > > > > > > > For each datatype in the "http://www.w3.org/2001/XMLSchema" > > namespace, > > > it > > > > defines a new datatype in the "http://www.w3.org/2001/XMLSchema- > > > datatypes" > > > > namespace, deriving it from the original by trivial restriction. > > > > > > > > You can import this schema like any other schema. It's often easier > > to > > > > simply use the predefined xs: prefix, which always points to > > > > "http://www.w3.org/2001/XMLSchema". > > > > > > > > Jonathan > > > > > > > > At 06:13 PM 2/18/2003 +0000, Caroline Rioux wrote: > > > > > > > > >Hi, > > > > > > > > > >I need some clarification on the namespaces used for constructors > > and > > > > >datatypes. > > > > > > > > > >In the F&O spec, section 1.5 it says: > > > > > > > > > >The URIs of the namespaces are: > > > > > * http://www.w3.org/2001/XMLSchema-datatypes for constructors > > > > > * http://www.w3.org/2002/11/xquery-operators for operators > > > > > * http://www.w3.org/2002/11/xquery-functions for functions. > > > > > > > > > >Which implies that constructors are in the > > > > >http://www.w3.org/2001/XMLSchema-datatypes namespace > > > > > > > > > >In XML Schema Part 2: Datatypes section 3.1 (Namespace > > Considerations) > > > > > > > > > > The *built-in* datatypes defined by this specification are > > designed > > > to be > > > > > used with the XML Schema definition language as well as other > > XML > > > > > specifications. To facilitate usage within the XML Schema > > definition > > > > > language, the *built-in* datatypes in this specification have > > the > > > > > namespace name: > > > > > > > > > > http://www.w3.org/2001/XMLSchema > > > > > > > > > > To facilitate usage in specifications other than the XML Schema > > > definition > > > > > language, such as those that do not want to know anything about > > > aspects of > > > > > the XML Schema definition language other than the datatypes, > > each > > > > > *built-in* datatype is also defined in the namespace whose URI > > is: > > > > > > > > > > http://www.w3.org/2001/XMLSchema-datatypes > > > > > > > > > > > > > > >Does this mean that either namespace can be used, even in the case > > of > > > > >construction? > > > > > > > > > >Thanks for any clarification, > > > > > > > > > >-- > > > > >Caroline Rioux, Software Engineer +44-1865-203192 > > > > >DecisionSoft Limited > > http://www.decisionsoft.com > > > > >XML Development and Services > > > > > > > > > > > > > > -- > > > Caroline Rioux, Software Engineer +44-1865-203192 > > > DecisionSoft Limited > > http://www.decisionsoft.com > > > XML Development and Services > > > > > > > > > -- > Caroline Rioux, Software Engineer +44-1865-203192 > DecisionSoft Limited http://www.decisionsoft.com > XML Development and Services
Received on Wednesday, 5 March 2003 15:15:25 UTC