> perhaps, depending on what a b c really are:

I was assuming they were element names. If so use

<xsl:variable name="i" select="index-of($seq/node-name(), QName('b'))"/>

Michael Kay
http://www.saxonica.com/
> 
> 
> <xsl:variable name="i" select="index-of($seq,b)[1]"/>
> 
> - everything before the first b
> select="$seq[position() lt $i]
> 
> - everything from the first b to the end
> select="$seq[position() ge $i]
> 
> - the position of the first b?
> 
> select="$i"
> 
> David
> 
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