xdmp:role-name is available in ML10 and so useful I need to replicate in 8 and 9...

role-name.xqy

xquery version "1.0-ml";
import module namespace sec="http://marklogic.com/xdmp/security" at "/MarkLogic/security.xqy";
    
declare function local:role-name(
  $role-id as xs:unsignedLong
) as xs:string {
  xdmp:invoke-function(
      function() { sec:get-role-names($role-id) },
      <options xmlns="xdmp:eval">
        <database>{xdmp:database("Security")}</database>
      </options>
  )
};