Re: [xsl] if child element does not exist stop generation

[Wendell Piez <wapiez@xxxxxxxxxxxxxxxx>]

At 06:20 AM 5/3/2005, David wrote:
> > Hi,
> >          You can do this using:
> >
> ><xsl:if test="*[self::length]"> or
>
> That is more easily written as
>
> <xsl:if test="length">
>
> >  or
> >
> > <xsl:if test="*[name() = 'length']">

Translations from XPath short to long syntax:

"length" is short for
   "child::length"
   (set of 'length' element children of context node)

"*[self::length]" is short for
   "child::*[self::length]
   (set of element children that have a 'length' element on the self axis)

"*[name() = 'length']" is short for
   "child::*[name() = 'length']"
   (set of element children that return 'length' as the result
    of the name() function with an implicit argument of "self::node()")

The xsl:if test works by evaluating the test expression and returning a 
Boolean; then depending on the Boolean value, the contents of the xsl:if 
are processed (or not). When the result is not already a Boolean, it is 
"coerced" using the XPath casting rules. All these tests work because the 
casting rule for a node-set to a Boolean is that the set is true if it has 
any members, false if it is empty.

Cheers,
Wendell


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Wendell Piez                            mailto:wapiez@xxxxxxxxxxxxxxxx
Mulberry Technologies, Inc.                http://www.mulberrytech.com
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