append count of duplicate strings in non-text output

Question

I'm using the w3c bibtex transform to generate a bibtex file, but unfortunately it's generating duplicate author keys for papers in the same year.

• Jones:2012
• Jones:2012

The problem template is named bibtex-label in the xslt.

How could I add in a per-author, per-year count value so that the bibtex-label can look something like this:

• Jones:2012a
• Jones:2012b

I can't find any good resources on doing this sort of thing, particularly with a non-xml output.

Example input (from here):

<rdf:RDF xmlns="http://www.w3.org/2001/02pd/rec54#"
    xmlns:contact="http://www.w3.org/2000/10/swap/pim/contact#"
    xmlns:dc="http://purl.org/dc/elements/1.1/"
    xmlns:doc="http://www.w3.org/2000/10/swap/pim/doc#"
    xmlns:mat="http://www.w3.org/2002/05/matrix/vocab#"
    xmlns:org="http://www.w3.org/2001/04/roadmap/org#"
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns:rec="http://www.w3.org/2001/02pd/rec54#">

    <REC rdf:about="http://www.w3.org/TR/1998/REC-DOM-Level-1-19981001">
        <dc:date>1998-10-01</dc:date>
        <dc:title>Document Object Model (DOM) Level 1</dc:title>
        <doc:versionOf rdf:resource="http://www.w3.org/TR/REC-DOM-Level-1"/>
        <editor rdf:parseType="Resource">
            <contact:fullName>Arnaud Le Hors</contact:fullName>
        </editor>
        <editor rdf:parseType="Resource">
            <contact:fullName>Scott Isaacs</contact:fullName>
        </editor>
        <editor rdf:parseType="Resource">
            <contact:fullName>Steve Byrne</contact:fullName>
        </editor>
        <editor rdf:parseType="Resource">
            <contact:fullName>Mike Champion</contact:fullName>
        </editor>
        <editor rdf:parseType="Resource">
            <contact:fullName>Gavin Nicol</contact:fullName>
        </editor>
        <editor rdf:parseType="Resource">
            <contact:fullName>Lauren Wood</contact:fullName>
        </editor>
        <editor rdf:parseType="Resource">
            <contact:fullName>Ian Jacobs</contact:fullName>
        </editor>
        <editor rdf:parseType="Resource">
            <contact:fullName>Robert Sutor</contact:fullName>
        </editor>
        <editor rdf:parseType="Resource">
            <contact:fullName>Jonathan Robie</contact:fullName>
        </editor>
        <editor rdf:parseType="Resource">
            <contact:fullName>Chris Wilson</contact:fullName>
        </editor>
        <editor rdf:parseType="Resource">
            <contact:fullName>Vidur Apparao</contact:fullName>
        </editor>
        <org:deliveredBy rdf:parseType="Resource">
            <contact:homePage rdf:resource="http://www.w3.org/DOM/Group/"/>
        </org:deliveredBy>
        <mat:hasErrata rdf:resource="http://www.w3.org/DOM/updates/REC-DOM-Level-1-19981001-errata.html"/>
    </REC>


    <REC rdf:about="http://www.w3.org/TR/1998/REC-html40-19980424">
        <rdf:type rdf:resource="http://www.w3.org/2001/02pd/rec54#Superseded"/>
        <dc:date>1998-04-24</dc:date>
        <dc:title>HTML 4.0 Specification</dc:title>
        <doc:versionOf rdf:resource="http://www.w3.org/TR/html40"/>
        <editor rdf:parseType="Resource">
            <contact:fullName>Arnaud Le Hors</contact:fullName>
        </editor>
        <editor rdf:parseType="Resource">
            <contact:fullName>Ian Jacobs</contact:fullName>
        </editor>
        <editor rdf:parseType="Resource">
            <contact:fullName>David Raggett</contact:fullName>
        </editor>
        <previousEdition rdf:resource="http://www.w3.org/TR/REC-html40-971218"/>
        <org:deliveredBy rdf:parseType="Resource">
            <contact:homePage rdf:resource="http://www.w3.org/MarkUp/"/>
        </org:deliveredBy>
        <mat:hasErrata rdf:resource="http://www.w3.org/MarkUp/html40-updates/REC-html40-19980424-errata.html"/>
    </REC>

</rdf:RDF>

Example output (full):

@TechReport{LeHors:1998,
  author = {Arnaud Le Hors and Scott Isaacs and Steve Byrne and Mike Champion and Gavin Nicol and Lauren Wood and Ian Jacobs and Robert Sutor and Jonathan Robie and Chris Wilson and Vidur Apparao},
  title  = {{Document Object Model (DOM) Level 1}},
  note = {\url{http://www.w3.org/TR/1998/REC-DOM-Level-1-19981001}. Latest version available at \url{http://www.w3.org/TR/REC-DOM-Level-1}},
  year = {1998},
  month = nov,
  bibsource = "http://www.w3.org/2002/01/tr-automation/tr.rdf",
  type = "Recommendation",
  institution = "W3C",
}

@TechReport{LeHors:1998,
  author = {Arnaud Le Hors and Ian Jacobs and David Raggett},
  title  = {{HTML 4.0 Specification}},
  note = {\url{http://www.w3.org/TR/1998/REC-html40-19980424}. Latest version available at \url{http://www.w3.org/TR/html40}},
  year = {1998},
  month = apr,
  bibsource = "http://www.w3.org/2002/01/tr-automation/tr.rdf",
  type = "Recommendation",
  institution = "W3C",
}

Desired output:

@TechReport{LeHors:1998a,
  author = {Arnaud Le Hors and Scott Isaacs and Steve Byrne and Mike Champion and Gavin Nicol and Lauren Wood and Ian Jacobs and Robert Sutor and Jonathan Robie and Chris Wilson and Vidur Apparao},
  title  = {{Document Object Model (DOM) Level 1}},
  note = {\url{http://www.w3.org/TR/1998/REC-DOM-Level-1-19981001}. Latest version available at \url{http://www.w3.org/TR/REC-DOM-Level-1}},
  year = {1998},
  month = nov,
  bibsource = "http://www.w3.org/2002/01/tr-automation/tr.rdf",
  type = "Recommendation",
  institution = "W3C",
}

@TechReport{LeHors:1998b,
  author = {Arnaud Le Hors and Ian Jacobs and David Raggett},
  title  = {{HTML 4.0 Specification}},
  note = {\url{http://www.w3.org/TR/1998/REC-html40-19980424}. Latest version available at \url{http://www.w3.org/TR/html40}},
  year = {1998},
  month = apr,
  bibsource = "http://www.w3.org/2002/01/tr-automation/tr.rdf",
  type = "Recommendation",
  institution = "W3C",
}

Answer 1

Firstly, to simplify your translate function for the safeSurname function, you could define two variables at the top of your XSLT, like so

<xsl:variable name="nameIn" 
   select="'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ.- 0123456789ñÑçÇáéíóúÃÉÃÓÚäëïöüÄËÃÖÜ'" />
<xsl:variable name="nameOut" 
   select="'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'" />

This would then allow you to write the more readable code to get the formatted surname

<xsl:variable name="safeSurname" select="translate($surname, $nameIn, $nameOut)" />

It becomes more clear when you see the code to generate the suffix, which can be achieved using the xsl:number function to count the number of preceding siblings with a matching year and surname. Note the use of the format attribute to output a letter rather than a number:

<xsl:number 
   value="count(preceding-sibling::rec:REC
      [substring-before(dc:date/text(), '-') = $date]
      [translate(substring-after(rec:editor[1]/contact:fullName, ' '), $nameIn, $nameOut) = $safeSurname]
   ) + 1" 
   format="a"/>

In this code $date is the year of the current REC element.

Here is the full matching template for bibtex-label. Note I have removed the call to the dc:date template with mode bibtex-year just to keep the code all in one template.

<xsl:template match="*" mode="bibtex-label">
  <xsl:variable name="surname" select="substring-after(rec:editor[1]/contact:fullName, ' ')"/>
  <xsl:variable name="safeSurname" select="translate($surname, $nameIn, $nameOut)" />
  <xsl:variable name="date"  select="substring-before(dc:date/text(), '-')"/>
  <xsl:value-of select="concat($safeSurname, ':', $date)" />
  <xsl:number value="count(preceding-sibling::rec:REC[substring-before(dc:date/text(), '-') = $date][translate(substring-after(rec:editor[1]/contact:fullName, ' '), $nameIn, $nameOut) = $safeSurname]) + 1" format="a"/>
</xsl:template>