Hi, I have my doubts about the expressions used at the “tertium non datur”-principle in the documentation [1]. Or the expression should be “$a or not($a)” or the rewritten expression should be “false()” .
[1]: https://docs.basex.org/wiki/XQuery_Optimizations#Pure_Logic Best regards, Rob Stapper Sent from Mail for Windows 10 -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
