declare 
    %templates:wrap %templates:default("language", "en")
function demo:hello($node as node(), $model as map(*), $language as xs:string, $user as xs:string) as xs:string {
    switch($language)
        case "de" return
            "Hallo " || $user
        case "it" return
            "Ciao " || $user
        default return
            "Hello " || $user
};