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Re: [xsl] template matching with modes, not seeing what I expect

2020-03-16 02:51:27
Hi Wendell and others, thanks for your suggestions.

I'm much more of a mathematician than logician, so I went with the following, 
which works, hooray:

<xsl:template name="testsections">
  <xsl:param name="top" />
  <xsl:for-each select="$top/*">
    <xsl:variable name="sects" as="xs:integer" select="count(child::section)" />
    <xsl:variable name="titles" as="xs:integer" select="count(child::title)" />
    <xsl:variable name="all" as="xs:integer" select="count(child::*)" />
    <xsl:choose>
      <xsl:when test="$sects = 0"><xsl:text>none</xsl:text></xsl:when>
      <xsl:when test="$sects + $titles = 
$all"><xsl:text>all</xsl:text></xsl:when>
      <xsl:otherwise><xsl:text>mixed</xsl:text></xsl:otherwise>
    </xsl:choose>
  </xsl:for-each>
</xsl:template>

I know child:: is overkill but I've had so much trouble with this simple 
requirement that I thought anything which adds clarity is good.

Thanks again

Stay safe out there
T

-----Original Message-----
From: Wendell Piez wapiez(_at_)wendellpiez(_dot_)com 
<xsl-list-service(_at_)lists(_dot_)mulberrytech(_dot_)com> 
Sent: Monday, 16 March 2020 7:24
To: xsl-list(_at_)lists(_dot_)mulberrytech(_dot_)com
Subject: Re: [xsl] template matching with modes, not seeing what I expect

Hey Trevor,

To add to your XPath arsenal, consider also the XPath 2.0 functions
exists() and empty().

Where you have, for example, not(not(section)), you might wish to rewrite as 
not(empty(child::section)) which is indeed the same as exists(child::section). 
This might help to expose all the logic.

Additionally, we have operators in XPath 2.0

union - same as | - e.g. (title union section) except - I mentioned (* except 
title) intersect  - works as you would expect --

and also the "is" operation for node identity ...

Mulberry Technologies Inc. Quick Reference to XPath 2.0:
http://mulberrytech.com/quickref/xpath2.pdf

Cheers, Wendell

On Sun, Mar 15, 2020 at 2:07 PM Trevor Nicholls 
trevor(_at_)castingthevoid(_dot_)com 
<xsl-list-service(_at_)lists(_dot_)mulberrytech(_dot_)com>
wrote:

Well the good news is that the simple test example I just created for 
you did copy the input document, although the subsects attributes were 
not all correctly filled in. While I work on chasing down the 
programming error that must be buried in there somewhere, I still have 
the problem of why my simple example incorrectly sets the attribute.

Adding debug content has shown that my test message is correctly 
constructing the temporary structure, so this problem lies in my tests 
for the type of content.

Given this for $tempstruct:

<section>
  <title />
  <section />
  <section />
</section>

the attribute should be "all"

Given this:

<section>
  <title />
  <para />
  <table />
  <para />
  <img />
</section>

the attribute should be "none"

and given this:

<section>
  <title>
  <section />
  <section />
  <para />
  <section />
</section>

the attribute should be "mixed"

The process I am using to try to get this result is ($tempstruct is 
passed in as the parameter "top"):

<xsl:template name="testsections">
  <xsl:param name="top" />
  <xsl:for-each select="$top/*">
    <xsl:choose>
      <xsl:when test="not(section)"><xsl:text>none</xsl:text></xsl:when>
      <xsl:when test="not(not(section) and 
not(title))"><xsl:text>all</xsl:text></xsl:when>
      <xsl:otherwise><xsl:text>mixed</xsl:text></xsl:otherwise>
    </xsl:choose>
  </xsl:for-each>
</xsl:template>

This template correctly identifies the all and none options, but 
returns "all" instead of "mixed" for the last example.

Tested on my full document (which has several hundred sections) I can 
see that all the "all" sections and all the "none" sections are 
correct, and all the "mixed" sections are erroneously reported as "all".

I thought the test "not(not(section) and not(title))" would be true 
for all elements that had only title and section children. Evidently 
that's not true.

I tried the test "child::*[not(self::title)][not(self::section)]" as 
an alternative, but that performed even worse.

I've missed some subtlety in evaluating presence and absence of 
specific child elements, and it's probably in an FAQ somewhere, but if 
it is I missed it.

cheers
T



-----Original Message-----
From: Martin Honnen martin(_dot_)honnen(_at_)gmx(_dot_)de 
<xsl-list-service(_at_)lists(_dot_)mulberrytech(_dot_)com>
Sent: Monday, 16 March 2020 0:53
To: xsl-list(_at_)lists(_dot_)mulberrytech(_dot_)com
Subject: Re: [xsl] template matching with modes, not seeing what I 
expect

Am 15.03.2020 um 11:04 schrieb Trevor Nicholls 
trevor(_at_)castingthevoid(_dot_)com:

I'm testing a simple stylesheet which implements a suggestion made 
in reply to my previous approach, i.e. that I could process the 
output of a document into a variable to test. When the stylesheet is 
just reporting the results, it works just fine, but when I combine 
it with templates which copy the input document and replace one 
attribute based on those tests, the input document is not being copied.

But if I run this stylesheet and give it an input file (with no 
subsects
attributes) which contains a parent with multiple sections and mixed 
content, only the first section is output with the attribute 
(incorrectly set to "none"), and the rest of the output XML is the 
result of the mode="check" versions of the templates, i.e. the only 
output is the initial XML header followed by a copy of the 
$tempstruct variable built when the context node is the top level 
element of the input document.. The default templates simply aren't 
executed.

Can you show us a minimal sample input together with the output you 
get and then one you want?






--
...Wendell Piez... ...wendell -at- nist -dot- gov...
...wendellpiez.com... ...pellucidliterature.org... ...pausepress.org...
...github.com/wendellpiez... ...gitlab.coko.foundation/wendell...
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