XSLT, 2nd Edition

[2.0] Quantified Expressions—some and every

XPath 2.0 provides the some and every operators to perform a test against a sequence. The some operator returns true if the test is true for at least one item in the sequence, while every returns false if the test is false for at least one item in the sequence. Here is an example of the two operators:

<?xml version="1.0"?>
<!-- some-every.xsl -->
<xsl:stylesheet version="2.0" 
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:xs="http://www.w3.org/2001/XMLSchema">

  <xsl:output method="text"/>
 
  <xsl:variable name="English-months" as="xs:string*"
    select="('January', 'February', 'March', 'April',
             'May', 'June', 'July', 'August', 
             'September', 'October', 'November', 
             'December')"/>

  <xsl:template match="/">
    <xsl:text>&#xA;An example of the XPath 2.0 every and </xsl:text>
    <xsl:text>some operators:&#xA;&#xA;</xsl:text>
    <xsl:text>  If ANY month name has a string-length() </xsl:text>
    <xsl:text>&#xA;    greater than 4, print 'Yes,' otherwise</xsl:text>
    <xsl:text>&#xA;    print 'No'&#xA;&#xA;         </xsl:text>

    <xsl:value-of 
      select="if (some $m in $English-months satisfies 
              (string-length($m) &gt; 4)) then 'Yes' else 'No'"/>

    <xsl:text>&#xA;</xsl:text>
    <xsl:text>&#xA;&#xA;  If EVERY month name has a string-</xsl:text>
    <xsl:text>length() &#xA;    greater than 4, print 'Yes,' </xsl:text>
    <xsl:text>otherwise&#xA;    print 'No'&#xA;&#xA;         </xsl:text>

    <xsl:value-of 
      select="if (every $m in $English-months satisfies 
 (string-length($m) &gt; 4)) then 'Yes' else 'No'"/> ...