不懂不懂还是不懂。写XSL，删除XML的子节点，并输出XML。。在线求解！！
运行修改了好几次，都没有正确的输出！！！在线等高手求解，感激不敬 啊啊啊
这个是我的XSL文件：
<?xml version="1.0" encoding="UTF-8"?>
<xsl:transform version="2.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent ="yes"/>
<xsl:template match="book">
<book>
<author>
<xsl:sequence select="author/text()"/>
</author>
<title>
<xsl:sequence select="title/text()">
</xsl:sequence>
</title>
<contents>
<xsl:call-template name="removelast">
<xsl:with-param name ="seq" select="contents/chapter" as="element(chapter)*"/>
</xsl:call-template>
</contents>
</book>
</xsl:template>
<xsl:template match="chapter" >
<xsl:call-template name="removelast">
<xsl:with-param name="seq" select="chapter"
as="element(chapter)*"/>
</xsl:call-template>
</xsl:template>
<xsl:template name="removelast" >
<xsl:param name="seq" as="element()*"/>
<xsl:choose>
<xsl:when test="empty($seq[position()])"/>
<xsl:otherwise>
<xsl:call-template name="removelast">
<xsl:with-param name="seq" select="$seq[position()>1]"/>
</xsl:call-template>
</xsl:otherwise>
</xsl:choose>
</xsl:template>
</xsl:transform>
这个是原来的XML文件：
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE book SYSTEM "book.dtd">
<book>
<author>Priscilla Walmsley</author>
<title>Definitive XML Schema</title>
<contents>
<chapter title="Schema: An Introduction"/>
<chapter title="A quick tour of XML Schema"/>
<chapter title="Namespaces"/>
<chapter title="Schema composition"/>
<chapter title="Instances and schemas"/>
</contents>
</book>
这个是通过XSL删除最后节点之后要求输出的XML文件：
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE book SYSTEM "book.dtd">
<book>
<author>Priscilla Walmsley</author>
<title>Definitive XML Schema</title>
<contents>
<chapter title="Schema: An Introduction"/>
<chapter title="A quick tour of XML Schema"/>
<chapter title="Namespaces"/>
<chapter title="Schema composition"/>
</contents>
</book>
这个是DTD文件：
<!ELEMENT book (author,title,contents)>
<!ELEMENT author (#PCDATA)>
<!ELEMENT title (#PCDATA)>
<!ELEMENT contents (chapter+)>
<!ELEMENT chapter EMPTY>
<!ATTLIST chapter title CDATA #REQUIRED>
------解决方案--------------------
http://www.java2s.com/Tutorial/XML/0100__XSLT-stylesheet/iftestnotpositionlast.htm
<xsl:if test="not(position()=last())">
