Re: [xsl] Simplify HAIRY xslt

[Wendell Piez <wapiez@xxxxxxxxxxxxxxxx>]

Hi Marcus,

When this kind of thing appears, the simplest solution is to isolate just 
the bit that changes from the rest of the code:

At 08:35 PM 5/13/2004, you wrote:
>   <xsl:template name="rule">
>     <xsl:param name="uri"/>
>     <xsl:variable name="prefix" select="../@prefix"/>
>
>     <res:choose>
>       <res:when test="*[name() = '{$prefix}:rule']">
>         <xsl:element name="{$prefix}:rule" namespace="{$uri}">
>           <xsl:if test="string(@display)">
>             <xsl:attribute name="displayValue">{<xsl:value-of 
> select="@display"/>}</xsl:attribute>
>           </xsl:if>
>           <xsl:attribute name="uid">{*[name() = '<xsl:value-of 
> select="$prefix"/>:rule']/@uid}</xsl:attribute>
>           <xsl:attribute name="xpath">{$newXpath}</xsl:attribute>
>           <xsl:attribute name="type">{$type}</xsl:attribute>
>           <xsl:copy-of select="@*|node()"/>
>         </xsl:element>
>       </res:when>
>       <res:otherwise>
>         <xsl:element name="{$prefix}:rule" namespace="{$uri}">
>           <xsl:if test="string(@display)">
>             <xsl:attribute name="displayValue">{<xsl:value-of 
> select="@display"/>}</xsl:attribute>
>           </xsl:if>
>           <xsl:attribute name="uid">{generate-id()}_<xsl:value-of 
> select="$prefix"/></xsl:attribute>
>           <xsl:attribute name="xpath">{$newXpath}</xsl:attribute>
>           <xsl:attribute name="type">{$type}</xsl:attribute>
>           <xsl:copy-of select="@*|node()"/>
>         </xsl:element>
>       </res:otherwise>
>     </res:choose>
>
>   </xsl:template>

  <xsl:template name="rule">
    <xsl:param name="uri"/>
    <xsl:variable name="prefix" select="../@prefix"/>

      <xsl:element name="{$prefix}:rule" namespace="{$uri}">
        <xsl:if test="string(@display)">
          <xsl:attribute name="displayValue">{<xsl:value-of 
select="@display"/>}</xsl:attribute>
        </xsl:if>
        <xsl:attribute name="uid">

    <res:choose>
      <res:when test="*[name() = '{$prefix}:rule']">
        <xsl:text>{*[name() = '</xsl:text>
        <xsl:value-of select="$prefix"/>
        <xsl:text>:rule']/@uid}</xsl:text>
      </res:when>
      <res:otherwise>
        <xsl:text>{generate-id()}_</xsl:text>
        <xsl:value-of select="$prefix"/>
      </res:otherwise>
    </res:choose>

        </xsl:attribute>
        <xsl:attribute name="xpath">{$newXpath}</xsl:attribute>
        <xsl:attribute name="type">{$type}</xsl:attribute>
        <xsl:copy-of select="@*|node()"/>
      </xsl:element>
  </xsl:template>

You can isolate this logic further:

  <xsl:template name="rule">
    <xsl:param name="uri"/>
    <xsl:variable name="prefix" select="../@prefix"/>
    <xsl:variable name="uid-assign">

    <res:choose>
      <res:when test="*[name() = '{$prefix}:rule']">
        <xsl:text>{*[name() = '</xsl:text>
        <xsl:value-of select="$prefix"/>
        <xsl:text>:rule']/@uid}</xsl:text>
      </res:when>
      <res:otherwise>
        <xsl:text>{generate-id()}_</xsl:text>
        <xsl:value-of select="$prefix"/>
      </res:otherwise>
    </res:choose>

    </xsl:variable>

      <xsl:element name="{$prefix}:rule" namespace="{$uri}">
        <xsl:if test="string(@display)">
          <xsl:attribute name="displayValue">{<xsl:value-of 
select="@display"/>}</xsl:attribute>
        </xsl:if>
        <xsl:attribute name="uid">
          <xsl:value-of select="$uid-assign"/>
        </xsl:attribute>
        <xsl:attribute name="xpath">{$newXpath}</xsl:attribute>
        <xsl:attribute name="type">{$type}</xsl:attribute>
        <xsl:copy-of select="@*|node()"/>
      </xsl:element>
  </xsl:template>

which can be handy for parameterization, shortening the syntax, etc.
(You will want to straighten up the indents in that code.)

I hope that helps.
Wendell


> Sorry about the long lines.
>
> Thanks
>
> /Marcus

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