anchor.diff:  
    . first reads and parses all files with '.xml' extension in 'flora' directory,
    . then collects all parsed documents into a new document whose document element is +<flora>...</flora>+,
  - . then transforms this document with XSLT stylesheet 'flora/to-genera.xsl',
  + . then transforms this document with XSLT stylesheet 'flora/styles/to-genera.xsl',
    . then finds all fragments from the resulted document which matches XPath criterion +/genera/genus+,
    . finally writes each fragment to a file whose path is 'flora-genera/XXX.xml', where +XXX+ is the string value of XPath expression +/genus/@name+ of each fragment document (that is, +XXX+ of the document element +<genus name="XXX">...</genus>+).
   
  
positive.code: |=================
  
  
  === All filter
  
  An _All_ filter receives XML documents, collects all of their document elements,
  
negative.code: <target name="flora-genera">
    <chionographis srcdir="flora" includes="*.xml">
      <all root="flora">
        <transform style="flora/styles/to-genera.xsl">
          <snip select="/genera/genus">
            <output destdir="flora/genera" refer="/genus/@name">
              <globmapper from="*" to="*.xml"/>
            </output>
          </snip>
  