Functions and recursion

xquery version "3.0"; declare function local:greet($name as xs:string, $lang as xs:string?) as xs:string { if ($lang = "de") then "Hallo " || $name else if ($lang = "es") then "Hola " || $name else "Hello " || $name }; local:greet("Susi", "de"), local:greet("Susi", "es"), local:greet("Susi", "en"), local:greet("Susi", ())

xquery version "1.0"; declare function local:fact($n as xs:integer) { if ($n eq 1) then $n else $n * local:fact($n - 1) }; local:fact(6)