Hi,
I have this script where I use the lookup operator to perform a unary lookup:
xquery version "3.1"; declare namespace array = "http://www.w3.org/2005/xpath-functions/array";
let $array := []
return ( empty($array!?*), (: returns false :) empty( for $i in 1 to array:size($array) return $array($i) ) (: returns true :) )
I'm curious that the first expression returns false even though it should be equivalent to the second expression, if I read the XQuery spec [1] right:
If the context item is an array:
If theKeySpecifier https://www.w3.org/TR/2017/REC-xquery-31-20170321/#doc-xquery31-KeySpecifieris a wildcard ("|*|"), theUnaryLookup https://www.w3.org/TR/2017/REC-xquery-31-20170321/#doc-xquery31-UnaryLookupoperator is equivalent to the following expression:
for $k in 1 to array:size(.) return .($k)
But maybe I'm missing something. I'd be glad if you could help.
Best regards, Sebastian Zimmer
[1] https://www.w3.org/TR/2017/REC-xquery-31-20170321/#id-unary-lookup
