> What is wrong with my syntax?

Er Nothing, I suspect.

The problem is nothing to do with parameters or variables

<xsl:apply-templates>
   <xsl:sort select="....some expression..." order="{$orderby}" />
</xsl:apply-templates>

works in the current xt at least in exactly the same way as

<xsl:apply-templates>
   <xsl:sort select="....some expression..." order="{'descending'}" />
</xsl:apply-templates>

which is to say it doesn't work at all.

In an AVT the expressions inside a { } are evaluated and coerced to
being strings, and one assumes (but it doesn't say in the spec) that
all such strings, and the characters outside of { } are joined together
with an implicit concat() to make a resulting string which is used
as the value of the AVT. In this interpretation 
     "{'descending'}" and "descending" 
would be equivalent.

What does the new saxon do (Michael?)

David


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