Re: test if null

> In case of absence of any text node, wouldn't the expression yield true? I  
> thought the string-length of an empty node-set would be 0.

Sorry yes you were right. (So my answer was less right than yours:-)
<xsl:if test="string-length(EMPTYNODE/text()) = 0">
is equivalent to 
<xsl:if test="EMPTYNODE/text()">
But this still probably is not what the OP wants.

David

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