Hi,
I think the following is a mistake in the doc, but before changing the wiki, I wanted to double-check.
The documentation for map:get says, "If the supplied key is the xs:float or xs:double value NaN, the function returns an empty sequence." BaseX 8.1 returns the value that corresponds to the NaN key (if present). The software behavior seems correct to me. For example:
INPUT
let $mymap := map:entry(xs:double('NaN'),'abc')
return map:get($mymap,xs:double('NaN'))
OUTPUT
abc
Thanks,
Amanda