August 2001
Intermediate to advanced
480 pages
11h 16m
English
not() Function — Returns the negation of its argument. If the argument is not a boolean value already, it is converted to a boolean value using the rules described in the boolean() function entry.
booleannot(boolean)
A boolean value, or more commonly, an XPath expression that evaluates to a boolean value.
false if the input parameter is true; true if the input parameter is false.
XPath section 4.3, Boolean Functions.
To demonstrate the not() function, we’ll use the same stylesheet and XML document we used for the boolean() function. Here’s our XML document:
<?xml version="1.0"?> <test> <p>This is a test XML document used by several of our sample stylesheets.</p> <question> <text>When completed, the Eiffel Tower was the tallest building in the world.</text> <true>Yes! The Eiffel Tower was the world's tallest building until 1932, when New York's Empire State Building opened. </true> <false>No, the Eiffel Tower was the world's tallest building for over 30 years.</false> </question> </test>
We’ll process this document with the following stylesheet, which uses the not() to negate all boolean() function calls:
<?xml version="1.0"?> <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:output method="text"/> <xsl:variable name="newline"> <xsl:text> </xsl:text> </xsl:variable> <xsl:template match="/"> <xsl:value-of select="$newline"/> <xsl:text>Tests of the not() function:</xsl:text> <xsl:value-of select="$newline"/> <xsl:value-of ...