//Whoohaa!
XPathExpression expr = nav.Compile("set:distinct(//author)");
expr.SetContext(new ExsltContext(doc.NameTable));
XPathNodeIterator authors = nav.Select(expr);
while (authors.MoveNext())
Console.WriteLine(authors.Current.Value);
EXSLT's set:distinct in XPath-only selection. Sweet.Coming soon, watch announcements!
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