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Re: newbie variable question
- To: xsl-list at mulberrytech dot com, XSL-List at mulberrytech dot com
- Subject: Re: newbie variable question
- From: "John E. Simpson" <simpson at polaris dot net>
- Date: Tue, 26 Sep 2000 14:14:53 -0400
- Reply-To: xsl-list at mulberrytech dot com
At 12:01 PM 09/26/2000 -0400, Les Howard wrote:
>if there are any grp/type element whose contents are "DMA" I want to
>print out the value of the associated name in that grp. if there is no
>grp/type element whose contents is "DMA" I want to print out the values
>of the description element.
>[XML:]
> <area>
> <grp>
> <type>MSA</type>
> <name>foo</type>
> </grp>
> <grp>
> <type>DMA</type>
> <name>bar</type>
> </grp>
> </area>
> <description>baz</description>
>
>[XSLT:]
> <xsl:for-each select="area/grp">
> <xsl:if test="string(type)='DMA'">
> <xsl:value-of select="name"/>
> <xsl:variable name="ValueExists" select="'True'"/>
> </xsl:if>
> </xsl:for-each>
><xsl:if test="$ValueExists!="'True'">
> <xsl:value-of select="description" />
></xsl:if>
>
>but I keep getting an error:
>
>A reference to variable or parameter 'ValueExists' cannot be resolved.
>The variable or parameter may not be defined, or it may not be in scope.
The error makes sense. XSLT variables are in effect ("in scope") only
within the block of code in which they're defined. Your stylesheet is
structured in part like this:
Begin for-each....
If some condition....
Define variable $ValueExists
End if
End for-each
If some condition....
Do something with $ValueExists
End if
See? The if-block doesn't know anything about $ValueExists. The second,
standalone if-block can't "see into" the if-block which contains the
variable's definition; the variable goes out of scope when that if-block
closes.
You can sometimes get around the problem by declaring the variable globally
-- that is, make the <xsl:variable...> element a top-level element (child
of <xsl:stylesheet>). I say sometimes because you can't always get at some
information that would be readily available from within a template rule.
Might be better in your case to simply instantiate one template for
type="DMA" and a different one for type!="DMA", using those expressions as
predicates.
==========================================================
John E. Simpson | "If you were going to
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