. I'd like to be able to do something along
the following lines in my stylesheet:

format('{#Add a new {0}#}',<xsl:value-of select='@n'/>)

Can anyone suggest how I could implement something like this?

<xsl:function name="f:format">
  <xsl:param name="fmt"/>
  <xsl:param name="val"/>
  <xsl:value-of select="$fmt,$val"/>
</xsl:function>

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