Re: [xsl] recursion

["Jim Albright jim_albright@xxxxxxxxxxxx" <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx>]

Michael,

Thank you!!! That fixed it.

Jim

-----Original Message-----
From: Michael Kay mike@xxxxxxxxxxxx
[mailto:xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx]
Sent: Thursday, January 24, 2019 3:42 AM
To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
Subject: Re: [xsl] recursion

>  $notes[$number] is always true

Minor correction. The effective boolean value of $number is always true, so
exists($notes[$number]) is equivalent to exists($notes).

Michael Kay
Saxonica

> On 24 Jan 2019, at 08:39, Michael Kay mike@xxxxxxxxxxxx
<xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx> wrote:
>
> I don't know if it's the cause of your problem, but you've fallen into a
classic elephant trap here by writing
>
>> <xsl:with-param name="number"><xsl:value-of select="$number +
1"/></xsl:with-param>
>
> instead of
>
>> <xsl:with-param name="number" select="$number + 1"/>
>
> Usually this is only a problem of code efficiency and readability, but in
this case it actually affects the logic. The way you have written it, $number
is a document node (or in 1.0, a result tree fragment), so $notes[$number] is
always true, because the effective boolean value of a node is always true. You
obviously intended this to be a numeric selection, which will only be the case
if $number is indeed a number.
>
> General rule: declare the types of your variables and parameters, and many
of your bugs will be found in a fraction of the time.
>
> Michael Kay
> Saxonica
>
>> On 24 Jan 2019, at 03:34, Jim Albright jim_albright@xxxxxxxxxxxx
<xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx> wrote:
>>
>> Problem:  I have an XML file that has notes mixed up with comments.  I want
to move the notes from current location to Notes element.  There could be 0 to
10 notes.
>> Solution:  I will first copy notes found in
>> span[@class='x']
>> from current location to Notes.  With a second XSLT I will delete the
unwanted ones.
>>
>>       <xsl:variable name="notes"
select="ancestor::Lexicon_Entry//LEXMeanings[1]//LEXSense[@LanguageCode='pt']
//span[@class='x']"/>
>>
>> Recursive code XSLT 2.0:
>>   <xsl:template name="get_note">
>>       <xsl:param name="notes" select="."/>
>>       <xsl:param name="number" ><xsl:value-of select="."/></xsl:param>
>>       number /<xsl:value-of select="$number"/>/
>>       notes[number] /<xsl:value-of select="$notes[$number]"/>/
>>       notes /<xsl:value-of select="$notes"/>/
>>       <xsl:choose>
>>           <xsl:when test="exists($notes[$number])">
>>               <xsl:element name="note">
>>               <xsl:attribute name="Caller"><xsl:value-of
select="$number"/></xsl:attribute>
>>               <xsl:attribute name="LanguageCode">pt</xsl:attribute>
>>               <xsl:element name="Content">
>>                   <xsl:copy-of select="$notes[$number]"/>
>>               </xsl:element>
>>           </xsl:element>
>>               <xsl:call-template name="get_note">
>>                   <xsl:with-param name="notes" select="$notes"/>
>>                   <xsl:with-param name="number"><xsl:value-of
select="$number + 1"/></xsl:with-param>
>>               </xsl:call-template>
>>           </xsl:when>
>>           <xsl:otherwise>
>>           zzzzzzzz    <!-- end -->
>>           </xsl:otherwise>
>>       </xsl:choose>
>>   </xsl:template>
>>
>> This works fine for 0 or 1 notes but when 2 or more are found it goes into
an endless loop.
>> Here is output with debugging code showing values
>>   <Note Caller="1" LanguageCode="en">
>>       <References/>
>>       <Content>There are no doubt certain subtle differences of meaning in
these terms, especially in their connotations, but it is not possible to
specify the difference on the basis of existing contexts.</Content>
>>     </Note>
>>   <Note Caller="1" LanguageCode="pt">
>>             <Content>
>>             <span class="x">2 Com certeza existem sutis diferenC'as de
significado entre esses termos, especialmente em termos conotativos, mas nC#o
C) possC-vel determinar isso com base nos contextos disponC-veis.
</span></Content></Note>
>>
>>
>> <note Caller="2" LanguageCode="pt"><Content><span class="x">3 Em Mt 5.21,
<span lang="gk">N:O
a=7ON9O</span> se refere, provavelmente, a um tribunal
local. </span></Content></note>
>>
>>
>>       number /3/
>>       notes[number] /2 Com certeza existem sutis diferenC'as de significado
entre esses termos, especialmente em termos conotativos, mas nC#o C) possC-vel
determinar isso com base nos contextos disponC-veis.  3 Em Mt 5.21,
N:O
a=7ON9O se refere, provavelmente, a um tribunal local. /
>>       notes /2 Com certeza existem sutis diferenC'as de significado entre
esses termos, especialmente em termos conotativos, mas nC#o C) possC-vel
determinar isso com base nos contextos disponC-veis.  3 Em Mt 5.21,
N:O
a=7ON9O se refere, provavelmente, a um tribunal local. /
>>
>> so when $number is 3, $notes[$number] is the same as $notes but $notes[3]
is the empty set.
>> I have verified that $number is actually an integer.  In this example there
are two notes. The first note starts with 2 Com ... and the second note starts
with 3 Em ...
>>
>> This puts me in an endless loop as it always finds something in
$notes[$number]
>>
>>
>> Jim Albright
>> 704-562-1529 unlimited cell
>> Wycliffe Bible Translators