Re: [xsl] compare two node sets

Subject: Re: [xsl] compare two node sets
From: "Piez, Wendell A. (Fed) wendell.piez@xxxxxxxx" <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx>
Date: Tue, 21 Jan 2020 15:41:56 -0000
Hi,

Another solution not yet suggested in this thread is to avoid deep-equal() and
rely on a signature function.

So for example,

<xsl:function name="f:signature" as="xs:string">
  <xsl:param name="who" as="node()"/>
  <xsl:value-of select="string-join($who/(first, last), ' ')"/>
</xsl:function>


Then your list of author-directors is
//author[f:signature(.)=parent::film/child::director/f:signature(.)]

(Or the other way around.)

Wrap the expression in the filter in not() to retrieve authors who did not
direct, etc.

One advantage of this approach is it's easy to adjust the signature logic to
real-world exigencies.

Cheers, Wendell

-----Original Message-----
From: Wolfhart Totschnig wolfhart.totschnig@xxxxxxxxxxx
<xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx>
Sent: Sunday, January 19, 2020 4:22 PM
To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
Subject: Re: [xsl] compare two node sets

Thank you, David, Michael, and Liam for the prompt replies! Michael's solution
seems to be the simplest to implement. I use Saxon 9 HE, so XPath 2.0 should
be okay. And, indeed, quadratic performance should not be an issue. However,
Saxon throws the following error:

XPST0003: Unexpected token "every" at start of expression

Is there a typo in the expression? I used the expression as given:

<xsl:when test="count(//director) eq count(//author) and every $d in
//director satisfies some $a in //author satisfies deep-equal($d/*, $a/*)">

To clarify, the context node is the <film> element.

Wolfhart


On 19.01.20 17:55, Liam R. E. Quin liam@xxxxxxxxxxxxxxxx wrote:
> On Sun, 2020-01-19 at 20:37 +0000, Wolfhart Totschnig
> wolfhart.totschnig@xxxxxxxxxxx wrote:
>> Hello,
>>
>> I have an XSL/XPath problem to which I cannot find the solution. I
>> have an xml file with data about films, in the following form
>> (simplified):
>>
>> [..]
>> . By contrast, in the following example the test should return
>> <false>:
>>
>>      <film>
>>         <title>M</title>
>>         <director>
>>            <first>Fritz</first>
>>            <last>Lang</last>
>>         </director>
>>         <author>
>>            <first>Thea von</first>
>>            <last>Harbou</last>
>>         </author>
>>         <author>
>>            <first>Fritz</first>
>>            <last>Lang</last>
>>         </author>
>>      </film>
> Why?
>
> As stated,
>   <xsl:mode on-no-match="shallow-copy" />
>
>    <xsl:template match="/">
>      <xsl:apply-templates select="/films/film[
>          some $a in author satisfies
>          (
>              ($a/first = director/first)
>              and ($a/last = director/last)
>          )
>      ]"/>
>    </xsl:template>
>
> Liam

Current Thread