Re: [xsl] Writing an optional element

[Wendell Piez <wapiez@xxxxxxxxxxxxxxxx>]

At 03:41 PM 7/5/2004, it was written:
>    Nestor> Is there a better way to do it than:
>
>     Nestor> <xsl:choose> <xsl:when test="condition"> <element>
>     Nestor> ... processing instructions ...  </element> </xsl:when>
>     Nestor> <xsl:otherwise> ... repeat processing instructions ...
>     Nestor> </xsl:otherwise> </xsl:choose>
>
> If by a better way, you mean you want to avoid writing the same
> "continue processing" code, then you could call a named template
> each time. Said named template to contain the common code.

Also, there are times when conditional logic can be handled by template 
matches:

<xsl:template match="span[@display='i']">
  <i>
    <xsl:apply-templates/>
  </i>
</xsl:template>

<xsl:template match="span">
  <xsl:apply-templates/>
</xsl:template>

Because the first template has a higher priority than the second, it will 
fire in preference to the second when the condition in the predicate is 
true; the second template catches those cases for which the condition isn't 
true.

Not every condition can be handled like this, due to restrictions on what 
may appear in patterns (e.g. no variable references are allowed). 
Nevertheless this is very useful, and certainly clean compared to those 
somewhat bloated choose/when/otherwise combinations.

Cheers,
Wendell


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Wendell Piez                            mailto:wapiez@xxxxxxxxxxxxxxxx
Mulberry Technologies, Inc.                http://www.mulberrytech.com
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Suite 207                                          Phone: 301/315-9631
Rockville, MD  20850                                 Fax: 301/315-8285
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