XPath error: Cannot select a node here: the context item is an atomic value
paul
posted @ Wed, 16 Mar 2011 22:24:18 +0800
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xpath Saxon XSLT
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Assume the input xml file is like
<people> <person> <name>paul</name> <gender>male</gender> </person> <person> <name>lee</name> <gender>female</gender> </person> </people>
This XPath error complained for the below style sheet.
<?xml version="1.0"?> <xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:template match="/"> <xsl:element name="team"> <xsl:for-each select="distinct-values(//gender)"> <xsl:variable name="gender" select="."/> <xsl:element name="{$gender}"> <xsl:for-each select="//person[gender=$gender]"> <!-- Wrong! A node is selected for actomic context item. --> <xsl:variable name="name" select="name"/> <xsl:element name="{$name}"/> </xsl:for-each> </xsl:element> </xsl:for-each> </xsl:element> </xsl:template> </xsl:stylesheet>
This error means that a node was selected for a actomic context item. The atomic context item is chosen by the outer for-each loop <xsl:for-each select="distinct-values(//gender)"/>.
Node items can not be selected in this loop context.
The solution is define a variable outside of loop. the variable value is the string of the node path. Then select the node with that variable.
<?xml version="1.0"?> <xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:template match="/"> <xsl:element name="team"> <xsl:variable name="person" select="//person"/> <!-- Define the variable with the node path. --> <xsl:for-each select="distinct-values(//gender)"> <xsl:variable name="gender" select="."/> <xsl:element name="{$gender}"> <xsl:for-each select="$person[gender=$gender]"> <!-- Select the node by the variable defined outside of this for-each loop. --> <xsl:variable name="name" select="name"/> <xsl:element name="{$name}"/> </xsl:for-each> </xsl:element> </xsl:for-each> </xsl:element> </xsl:template> </xsl:stylesheet>
Weird enough, but seems like the only available solution.
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