[XSL-LIST Mailing List Archive Home] [By Thread] [By Date]

RE: [xsl] advice on node-set fallback needed


Subject: RE: [xsl] advice on node-set fallback needed
From: "Michael Kay" <mhk@xxxxxxxxx>
Date: Tue, 19 Aug 2003 14:04:49 +0100

XSLT 1.0 allows you to specify version on the xsl:stylesheet element, or
xsl:version on a literal result element. Unfortunately there is no way
of scoping the version to less than a whole stylesheet module unless you
have a convenient LRE. This anomaly is fixed in 2.0, but that's too late
for you. Putting version="2.0" on xsl:value-of should be an error under
1.0, unless there's a version="2.0" on the xsl:stylesheet, in which case
its pointless!

Michael Kay

> -----Original Message-----
> From: owner-xsl-list@xxxxxxxxxxxxxxxxxxxxxx 
> [mailto:owner-xsl-list@xxxxxxxxxxxxxxxxxxxxxx] On Behalf Of 
> Julian Reschke
> Sent: 19 August 2003 09:20
> To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
> Subject: RE: [xsl] advice on node-set fallback needed
> 
> 
> Thanks Mike.
> 
> > Are you saying MSXML4 gives you a compile-time error for a path 
> > expression that misuses an RTF?
> 
> Yes.
> 
> > The XSLT 1.0 spec is very unspecific about which errors are 
> > compile-time errors and which are run-time. The spec merely 
> says that 
> > this operation "is not permitted". But you should be able 
> to get it to 
> > compile by using forwards-compatible mode, which you can invoke by 
> > setting version="2.0" (or any value other than 1.0).
> 
> So I'm now trying:
> 
>   <xsl:choose>
>     <xsl:when test="function-available('exsl:node-set')">
> 	    <xsl:text>exsl: </xsl:text><xsl:value-of 
> select="name(exsl:node-set($test)/node())" />
>     </xsl:when>
>     <xsl:when test="function-available('msxsl:node-set')">
> 	    <xsl:text>msxsl: </xsl:text><xsl:value-of 
> select="name(msxsl:node-set($test)/node())" />
>     </xsl:when>
>     <xsl:otherwise>
> 	    <xsl:text>(none): </xsl:text><xsl:value-of 
> version="2.0" select="name($test/node())" />
>    </xsl:otherwise>
>   </xsl:choose>
> 
> However this breaks execution in Saxon 6.5.3 and MSXML completely:
> 
> (MSXML3 and MSXML4)
> 
> Error occurred while compiling stylesheet 'test.xslt'.
> 
> Code:   0x80004005
> Attribute 'version' is invalid on 'xsl:value-of'.
> 
> (Saxon)
> 
>   Attribute version is not allowed on this element 
> Transformation failed: Failed to compile stylesheet. 1 error detected.
> 
> 
> Using xsl:version instead of version yields:
> 
> (MSXML3)
> 
> Works.
> 
> (MSXML4)
> 
> Error occurred while compiling stylesheet 'test.xslt'.
> 
> Code:   0x80004005
> Expression must evaluate to a node-set.
> 
> name(-->$test<--/node())
> 
> (Saxon)
> 
>   Attribute xsl:version is not allowed on this element 
> Transformation failed: Failed to compile stylesheet. 1 error detected.
> 
> 
> What *does* seem to work is setting version="2.0" on the 
> stylesheet element itself. However I'm a bit concerned that 
> this will instruct an XSLT 2.0 in a non-XSLT-1.0 compatible manner.
> 
> However, this:
> 
>   <xsl:choose>
>     <xsl:when test="function-available('exsl:node-set')">
> 	    <xsl:text>exsl: </xsl:text><xsl:value-of 
> select="name(exsl:node-set($test)/node())" />
>     </xsl:when>
>     <xsl:when test="function-available('msxsl:node-set')">
> 	    <xsl:text>msxsl: </xsl:text><xsl:value-of 
> select="name(msxsl:node-set($test)/node())" />
>     </xsl:when>
>     <xsl:when test="system-property('xsl:version') &gt;= 2.0">
> 	    <xsl:text>(XSLT2.0): </xsl:text><xsl:value-of 
> version="2.0" select="name($test/node())" />
>     </xsl:when>
>     <xsl:otherwise>
> 	    <xsl:text>no way</xsl:text>
>    </xsl:otherwise>
>   </xsl:choose>
> 
> seems to work with all 1.0 processors I tried, and should 
> also work on an XSLT-2.0 processor without exslt:node-set(), right?
> 
> > The rules for what a 2.0 processor should do when given a 
> stylesheet 
> > that says version="1.0" have not fully stabilised, but the next 
> > version of the spec is likely to say that the processor 
> should give a 
> > warning about possible incompatibilities, and then execute the 
> > stylesheet in backwards-compatible mode. It should not 
> disallow use of 
> > 2.0 features just because the stylesheet says 
> version="1.0". In this 
> > case, however, your stylesheet is using a 2.0 feature so it 
> should say 
> > version="2.0".
> >
> > Michael Kay
> 
> Thank for the help,
> 
> Julian
> 
> --
> <green/>bytes GmbH -- http://www.greenbytes.de -- tel:+492512807760
> 
> 
>  XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list
> 


 XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list



Current Thread
Keywords