unique() function?

I thought I remembered that W3C XQuery had a unique() function that would return a sequence identical to its arguments except with duplicate items removed, but I can’t find it in either the Tamino or W3C documentation. Is this just my imagination, or was it there and then removed, or is it there and I just can’t find it?

(For people familiar with ADABAS/NATURAL, what I’m really looking for is the equivalent of a HISTOGRAM.)

Hi Curtis,

XQuery offers a distinct-values() function to get rid of duplicates
in lists of atomic values. A list of nodes $nl is made unique by
making it a path expression, for instance $nl/., but this also sorts
it in document order. Tamino does currently not offer the
distinct-values() function but will do so in the next version.