Functions

The current spec only allows functions to be either built in or defined in
the query in which they are used. I think it would be very useful to allow
functions to be imported just like schemas are imported. This would allow
authors to create a library of functions and include them in their query
without the need to duplicate them or make the global (or built-in)

How about?
ImportFunctions    ::=   <"import" "functions" "at"> StringLiteral

Regards,
Eddie