support gMonthDay, gDay

xquery/date.xqm

@@ -51,6 +51,8 @@ declare %private function date:getCastableDate($date as xs:string, $latest as xs
     else if($date castable as xs:gYearMonth) then
         if($latest) then xs:date(concat($date, '-', functx:days-in-month(xs:date(concat($date,'-01')))))
         else xs:date(concat($date,'-01'))
+    else if($date castable as xs:gMonthDay) then xs:date(concat('9999-', substring-after($date, '--')))
+    else if($date castable as xs:gDay) then xs:date(concat('9999-12-', substring-after($date, '---')))
     else()
 };
 
@@ -137,6 +139,8 @@ declare function date:printDate($date as element()?, $lang as xs:string, $get-la
                 if($date/@when castable as xs:date) then date:format-date($date/@when, $picture-string, $lang)
                 else if($date/@when castable as xs:gYear) then date:formatYear($date/@when, $lang)
                 else if($date/@when castable as xs:gYearMonth) then date:format-date(date:getCastableDate(data($date/@when),true()),'[MNn] [Y]', $lang)
+                else if($date/@when castable as xs:gMonthDay) then $get-language-string('noYear',xs:string(date:format-date(date:getCastableDate(data($date/@when),true()),'[D]. [MNn]', $lang)))
+                else if($date/@when castable as xs:gDay) then $get-language-string('noYearMonth',xs:string(date:format-date(date:getCastableDate(data($date/@when),true()),'[D].', $lang)))
                 else if($date/@when castable as xs:dateTime) then date:format-date(datetime:date-from-dateTime($date/@when), $picture-string, $lang)
                 else error($date:DATE_FORMAT_ERROR, 'unsupported value for @when: "' || $date/@when || '".')
            (:  @when-iso für die busoni-app :)
@@ -144,6 +148,8 @@ declare function date:printDate($date as element()?, $lang as xs:string, $get-la
                 if($date/@when-iso castable as xs:date) then date:format-date($date/@when-iso, $picture-string, $lang)
                 else if($date/@when-iso castable as xs:gYear) then date:formatYear($date/@when-iso, $lang)
                 else if($date/@when-iso castable as xs:gYearMonth) then date:format-date(date:getCastableDate(data($date/@when-iso),true()),'[MNn] [Y]', $lang)
+                else if($date/@when-iso castable as xs:gMonthDay) then $get-language-string('noYear',xs:string(date:format-date(date:getCastableDate(data($date/@when-iso),true()),'[D]. [MNn]', $lang)))
+                else if($date/@when-iso castable as xs:gDay) then $get-language-string('noYearMonth',xs:string(date:format-date(date:getCastableDate(data($date/@when-iso),true()),'[D].', $lang)))
                 else if($date/@when-iso castable as xs:dateTime) then date:format-date(datetime:date-from-dateTime($date/@when-iso), $picture-string, $lang)
                 else error($date:DATE_FORMAT_ERROR, 'unsupported value for @when-iso: "' || $date/@when-iso || '".')                         
             else if(exists($notBefore)) then