Saxon XSLT and XQuery Processor

Makes sense - though on the whole, someone who uses mode="#current" is a 
pretty advanced user of templates and modes, so it's not a mistake that 
many people are likely to make.

Michael Kay
Saxonica

On 10/12/2012 23:00, Imsieke, Gerrit, le-tex wrote:
> It would be nice if Saxon warned about the use of an xsl:apply-templates
> in mode="#current" from within a function’s sequence constructor.
>
> Or am I the only one who writes a function that is expected to be called
> in a certain mode, who uses apply-templates in the function body, who
> wants that apply-templates to take place in the same mode as the
> function happened to be invoked in – but who erroneously uses
> mode="#current" in the function (which selects the default mode).
>
> Is there a use case for mode="#current" in a function body anyway?
>
> (Don’t get me wrong, I don’t want to rule #current out or change its
> semantics within function declarations; I’d just appreciate if Saxon
> warned me, if that’s a reasonable thing to do in these circumstances.)
>
> Gerrit
>
> ------------------------------------------------------------------------------
> LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial
> Remotely access PCs and mobile devices and provide instant support
> Improve your efficiency, and focus on delivering more value-add services
> Discover what IT Professionals Know. Rescue delivers
> http://p.sf.net/sfu/logmein_12329d2d
> _______________________________________________
> saxon-help mailing list archived at http://saxon.markmail.org/
> saxon-help@...
> https://lists.sourceforge.net/lists/listinfo/saxon-help
>

On 2012-12-11 01:26, Michael Kay wrote:
> Makes sense - though on the whole, someone who uses mode="#current" is a
> pretty advanced user of templates and modes, so it's not a mistake that
> many people are likely to make.

Well, I did.

And although it wasn’t the first time for me to commit this mistake, it 
took (again) quite a considerable time to detect it.

On 10/12/2012 23:00, Imsieke, Gerrit, le-tex wrote:
> It would be nice if Saxon warned about the use of an xsl:apply-templates
> in mode="#current" from within a function’s sequence constructor.
>
> Or am I the only one who writes a function that is expected to be called
> in a certain mode, who uses apply-templates in the function body, who
> wants that apply-templates to take place in the same mode as the
> function happened to be invoked in – but who erroneously uses
> mode="#current" in the function (which selects the default mode).
>
A simple solution for a testing-phase runtime check would be something like:

<xsl:template name="checkCurrent">
         <xsl:variable name="cases" 
select="document('')//xsl:function[.//xsl:apply-templates[@mode='#current']]"/>
         <xsl:if test="exists($cases)">
             <xsl:message select="'Warning Dr. Smith - #current used in 
functions: ',$cases/string(@name)"/>
         </xsl:if>
     </xsl:template>

which would be called immediately on the main root match.

It would get a little more complex threading the importation/inclusion 
tree, but not overly so. This is one of those cases where XSLT being 
written in XML makes writing checking routines a joy.

-- 
John Lumley MA PhD CEng FIEE
john@...
+44 (0)1275 845284
mobile: +44 7765 717073

On 10/12/2012 23:00, Imsieke, Gerrit, le-tex wrote:
> It would be nice if Saxon warned about the use of an xsl:apply-templates
> in mode="#current" from within a function’s sequence constructor.
>
> Or am I the only one who writes a function that is expected to be called
> in a certain mode, who uses apply-templates in the function body, who
> wants that apply-templates to take place in the same mode as the
> function happened to be invoked in – but who erroneously uses
> mode="#current" in the function (which selects the default mode).
>
A simple solution for a testing-phase runtime check would be something like:

<xsl:template name="checkCurrent">
         <xsl:variable name="cases" 
select="document('')//xsl:function[.//xsl:apply-templates[@mode='#current']]"/>
         <xsl:if test="exists($cases)">
             <xsl:message select="'Warning Dr. Smith - #current used in 
functions: ',$cases/string(@name)"/>
         </xsl:if>
     </xsl:template>

which would be called immediately on the main root match.

It would get a little more complex threading the importation/inclusion 
tree, but not overly so. This is one of those cases where XSLT being 
written in XML makes writing checking routines a joy.

-- 
John Lumley MA PhD CEng FIEE
john@...
+44 (0)1275 845284
mobile: +44 7765 717073