Re: [xsl] transforming XSLT files to use XSLT3 features

["Martin Honnen martin.honnen@xxxxxx" <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx>]

Am 2/11/2023 um 12:57 PM schrieb John Lumley john@xxxxxxxxxxxx:
> On 11/02/2023 11:34, Chris Papademetrious
> christopher.papademetrious@xxxxxxxxxxxx wrote:
> > The approach is limited by its use of template matches and regular
> > expressions. For some reason, I donbt feel inclined to write an XPath
> > grammar parser in XSLT. But still, some low-hanging fruit can be
> > obtained.
>
> Have a look at Gunther Rademacher's REx Parser Generator
> https://www.bottlecaps.de/rex/
>
> It can be used to generate an XSLT parser for XPath 2. (I've used it
> extensively in the past for analysing XPath 3 expressions.)
>
> An alternative, if your XSLT platform supports it, is to use an
> InvisibleXML parser https://invisiblexml.org/
> There is an iXML grammar forB  XPath3.1 available
> (https://github.com/invisibleXML/ixml/tree/master/samples/XPath) which
> will also parse XPath2. You may be able to experiment with this using
> Martin Honnen's XSLT3 Fiddle
> (https://martin-honnen.github.io/xslt3fiddle/) which supports
> invisibleXML parsing functions.
Note that the entry page to the XSLT 3 fiddle with support for Invisible
XML through John's library is not
https://martin-honnen.github.io/xslt3fiddle/ but
https://martin-honnen.github.io/xslt3fiddle/index-iXML.html. There you
could then make use of the XPath 3.1 grammar with code like e.g.

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
B  version="3.0"
B  xmlns:xs="http://www.w3.org/2001/XMLSchema";
B  xmlns:jwL="https://github.com/johnlumley";
B  exclude-result-prefixes="#all"
B  expand-text="yes">

B  <xsl:include
href="https://martin-honnen.github.io/xslt3fiddle/xslt/jwiXML.processor.xsl"/
>

B  <xsl:param name="xpath31-grammar-uri"
as="xs:string">https://raw.githubusercontent.com/invisibleXML/ixml/master/sam
ples/XPath/XPath.reducedTree.ixml</xsl:param>

B  <xsl:variable name="parsed-xpath31-grammar"
select="jwL:compileGrammar(unparsed-text($xpath31-grammar-uri))"/>

B  <xsl:mode on-no-match="shallow-copy"/>

B  <xsl:output cdata-section-elements="parsed-tree"/>

B  <xsl:template match="xpath">
B B B  <xsl:copy>
B B B B B  <input>{.}</input>
B B B B B  <parsed-tree>{jwL:parse($parsed-xpath31-grammar, .)?tree =>
serialize(map{'method':'xml','indent':true()})}</parsed-tree>
B B B  </xsl:copy>
B  </xsl:template>

</xsl:stylesheet>


and parse e.g.

<root>
B  <examples>
B B B  <xpath>random-number-generator()?permute(1 to 5)</xpath>
B  </examples>
</root>

into


<root>
B  <examples>
B B B  <xpath><input>random-number-generator()?permute(1 to
5)</input><parsed-tree><![CDATA[<XPath>
B B  <PostfixExpr>
B B B B B  <FunctionCall>
B B B B B B B B  <UnprefixedName LocalPart="random-number-generator"/>
B B B B B B B B  <ArgumentList/>
B B B B B  </FunctionCall>
B B B B B  <Lookup>
B B B B B B B B  <KeySpecifier Name="permute"/>
B B B B B  </Lookup>
B B B B B  <ArgumentList>
B B B B B B B B  <RangeExpr>
B B B B B B B B B B B  <IntegerLiteral>1</IntegerLiteral>
B B B B B B B B B B B  <IntegerLiteral>5</IntegerLiteral>
B B B B B B B B  </RangeExpr>
B B B B B  </ArgumentList>
B B  </PostfixExpr>
</XPath>]]></parsed-tree></xpath>
B  </examples>
</root>