added some examples of XMLPQF to XMLPQF query rewrites

look in the first comments of the stylesheet to see how it is run.
probably this is the wrong place, but I checked it in here since I do not know of a better place.

diff --git a/util/pqf2pqf.xsl b/util/pqf2pqf.xsl
new file mode 100644 (file)
index 0000000..0457714
--- /dev/null
+++ b/util/pqf2pqf.xsl
@@ -0,0 +1,150 @@
+<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+  version="1.0">
+
+  <xsl:output indent="yes" method="xml" version="1.0" encoding="UTF-8"/>
+
+  <!--
+./yaz-xmlquery -p '@and @attr 1=1016 @attr 4=2 @attr 6=3 the @attr 1=4 fish' > test.xml && xsltproc identity.xsl test.xml && ./yaz-xmlquery -x test1.xml && xsltproc pqf2pqf.xsl test.xml |tee test2.xml && ./yaz-xmlquery -x test2.xml 
+
+./yaz-xmlquery -p '@not @attr 1=1016 @attr 4=2 @attr 6=3 @attr 7=1 @attr 8=4 fish @attr 1=4 fish' > test.xml && xsltproc identity.xsl test.xml && ./yaz-xmlquery -x test.xml && xsltproc pqf2pqf.xsl test.xml |tee test2.xml && ./yaz-xmlquery -x test2.xml 
+  -->
+
+  <!-- disable default templates -->
+  <xsl:template match="text()"/>
+  <xsl:template match="node()"/>
+
+  <!-- identity stylesheet templates -->
+  <xsl:template match="/query">
+    <query>
+      <xsl:apply-templates/>
+    </query>
+  </xsl:template>
+
+  <xsl:template match="rpn">
+    <rpn>
+      <xsl:attribute name="set">
+        <xsl:value-of  select="@set"/>
+      </xsl:attribute>
+      <xsl:apply-templates/>
+    </rpn>
+  </xsl:template>
+
+
+  <xsl:template match="apt">
+    <apt>
+      <xsl:apply-templates select="attr"/>
+      <xsl:apply-templates select="term"/>
+      <!-- re-ordering @attr's if you use the following -->
+      <!--
+      <xsl:apply-templates select="attr[@type=1]"/>
+      <xsl:apply-templates select="attr[@type=2]"/>
+      <xsl:apply-templates select="attr[@type=4]"/>
+      <xsl:apply-templates select="attr[@type=5]"/>
+      <xsl:apply-templates select="attr[@type=6]"/>
+      <xsl:apply-templates select="attr[@type=7]"/>
+      <xsl:apply-templates select="attr[@type=8]"/>
+      <xsl:apply-templates select="attr[@type=9]"/>
+      <xsl:apply-templates select="term"/>
+      -->
+    </apt>
+  </xsl:template>
+
+  <xsl:template match="operator">
+    <operator>
+      <xsl:attribute name="type">
+        <xsl:value-of  select="@type"/>
+      </xsl:attribute>
+      <xsl:apply-templates/>
+    </operator>
+  </xsl:template>
+
+  <xsl:template match="attr">
+    <xsl:copy-of select="."/>
+  </xsl:template>
+
+  <xsl:template match="term">
+    <xsl:copy-of select="."/>
+  </xsl:template>
+
+
+  <!-- special rewrite templates -->
+
+  <!-- attribute rewrites --> 
+
+  <!-- remove all @attr 6=3 with bracket syntax -->
+  <xsl:template match="attr[@type=6][@value=3]">
+  </xsl:template>
+
+  <!-- remove all @attr 6=4 with and syntax -->
+  <xsl:template match="attr[@type=6 and @value=4]">
+  </xsl:template>
+
+  <!-- rewrite all @attr 4=2 to @attr 4=1 -->
+  <xsl:template match="attr[@type=4][@value=2]">
+    <attr type="4" value="1"/>
+  </xsl:template>
+
+  <!-- rewrite all @attr 1=1016 to @attr 1=1016 @attr 6=2 -->
+  <xsl:template match="attr[@type=1 and @value=1016]">
+    <attr type="1" value="1016"/>
+    <attr type="6" value="2"/>
+  </xsl:template>
+
+
+
+  <!-- term rewrites -->
+
+  <!-- rewrite general term fish to squid -->
+  <xsl:template match="term[@type='general'][text()='fish']">
+    <term type="general">squid</term>
+  </xsl:template>
+
+
+  <!-- operator rewrites -->
+  <!-- nasty rewrite 'not' operator to 'and' operator -->
+  <!--
+  <xsl:template match="operator[@type='not']">
+    <operator>
+      <xsl:attribute name="type">
+        <xsl:value-of  select="'and'"/>
+      </xsl:attribute>
+      <xsl:apply-templates/>
+    </operator>
+  </xsl:template>
+  -->
+
+  <!-- remove 'not' operator, use first <apt> only -->
+  <xsl:template match="operator[@type='not']">
+    <xsl:apply-templates select="apt[1]"/>
+  </xsl:template>
+  
+
+
+  <!-- more nasty things for special occasions 
+       depending on multiple attribute combinations -->
+
+  <!-- whenever there is a <apt> containing a @attr 7 and a @attr 8,
+       rewrite these and drop all @attr 3, 
+       finally sort all other @attrs according to type 
+       and call all terms, still rewriting 'fish' to 'squid' -->
+ 
+ <xsl:template match="apt[attr/@type=7 and attr/@type=8]">
+   <apt>
+      <xsl:apply-templates select="attr[@type=1]"/>
+      <xsl:apply-templates select="attr[@type=2]"/>
+      <xsl:apply-templates select="attr[@type=4]"/>
+      <xsl:apply-templates select="attr[@type=5]"/>
+      <xsl:apply-templates select="attr[@type=6]"/>
+      <attr type="7" value="2"/>
+      <attr type="8" value="5"/>
+      <xsl:apply-templates select="attr[@type=9]"/>
+      <xsl:apply-templates select="term"/>
+   </apt>
+  </xsl:template>
+
+
+
+
+</xsl:stylesheet>
+
+