Re: Boolean true() and false() as strings?

[Wendell Piez <wapiez at mulberrytech dot com>]

John--

It's not the boolean test that's coercing $units_gt_300 to a string ...
it's the original <xsl:value-of select="true()"/> -- or false() -- that
creates it....

  "The xsl:value-of element is instantiated to create a text node in 
   the result tree. The required select attribute is an expression; 
   this expression is evaluated and the resulting object is converted 
   to a string as if by a call to the string() function." [XSLT 7.6.1]

Note this is different from saying
  <xsl:variable name="units_gt_300" select="true()"/>
where the assigned value is the Boolean.

Obscure little corners of the spec....

Cheers,
Wendell

At 04:17 PM 10/5/00 -0400, you wrote:
>A curious thing (well, to me!)... consider this template rule:
>
><xsl:template match="sales">
>   <h2>Regions Selling More than 300 Units:</h2>
>   <xsl:for-each select="region">
>     <xsl:variable name="units_gt_300">
>       <xsl:choose>
>         <xsl:when test="number(units) &gt; 300">
>           <xsl:value-of select="true()"/>
>         </xsl:when>
>         <xsl:otherwise>
>           <xsl:value-of select="false()"/>
>         </xsl:otherwise>
>       </xsl:choose>
>     </xsl:variable>
>     <xsl:if test="$units_gt_300='true'">
>       <h3><xsl:value-of select="concat(@name, ' (', units, '
units)')"/></h3>
>     </xsl:if>
>   </xsl:for-each>
></xsl:template>
>
>Note the assignment of Boolean true() or false() to the variable, and the 
><xsl:if> test. Why can't the latter be simply:
>
>   <xsl:if test="$units_gt_300">
>
>i.e., why the need to test vs. the string value "true"? Does using the 
>true() and false() functions in a variable coerce their return values to 
>string type rather than their "native" Boolean?


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Wendell Piez                            mailto:wapiez@mulberrytech.com
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