You could frame it as follows:

For each <line> containing "A", output the line and following siblings
having the same number of following siblings containing "B".

<xsl:for-each select="/lines/line[contains(., 'A')]">
	<xsl:variable name="b-count"
select="count(following-sibling::*[contains(., 'B')])"/>
	<xsl:copy-of select="."/>
	<xsl:copy-of
select="following-sibling::*[count(following-sibling::*[contains(.,
'B')]) = $b-count]"/>
</xsl:for-each>

-Brandon :)


On Fri, May 6, 2011 at 5:13 AM, Hermann Stamm-Wilbrandt
<STAMMW@xxxxxxxxxx> wrote:
> Hello,
>
> I know that this is basic but I cannot get it done correctly.
>
> Input:
> <lines>
>  <line></line>
>  <line>A1</line>
>  <line>1</line>
>  <line>B1</line>
>  <line></line>
>  <line>A2</line>
>  <line>2</line>
>  <line>2</line>
>  <line>2</line>
>  <line>B2</line>
>  <line></line>
>  <line></line>
> </lines>
>
> Intended output (blockwise, start at A, all including next B):
> <line>A1</line>
> <line>1</line>
>
> <line>A2</line>
> <line>2</line>
> <line>2</line>
> <line>2</line>
>
>
> This
>    <xsl:for-each select="/lines/line[contains(.,'A')]">
>      <xsl:copy-of select="."/>
>    </xsl:for-each>
> gives
> <line>A1</line>
> <line>A2</line>
>
> And this output is too much (double output of 2nd block)
> $ xsltproc y.xsl lines.xml | tidy -q -xml
> <line>A1</line>
> <line>1</line>
> <line />
> <line>A2</line>
> <line>2</line>
> <line>2</line>
> <line>2</line>
> <line />
> <line />
> <line>A2</line>
> <line>2</line>
> <line>2</line>
> <line>2</line>
> <line />
> <line />
>
> $ cat y.xsl
> <xsl:stylesheet version="1.0"
>  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
>>
>  <xsl:output omit-xml-declaration="yes"/>
>
>  <xsl:template match="/">
>    <xsl:for-each select="/lines/line[contains(.,'A')]">
>      <xsl:copy-of select="."/>
>      <xsl:copy-of select="following-sibling::*[not(contains(.,'B'))]"/>
>    </xsl:for-each>
>  </xsl:template>
>
> </xsl:stylesheet>
> $
>
> I tried making use of "preceding-sibling::*" at different places without
> success sofar.
> Any help is appreciated.
>
>
> Mit besten Gruessen / Best wishes,
>
> Hermann Stamm-Wilbrandt
> Developer, XML Compiler, L3
> Fixpack team lead
> WebSphere DataPower SOA Appliances
> https://www.ibm.com/developerworks/mydeveloperworks/blogs/HermannSW/
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