handle unless in arrays..

[KlavsKlavsen]

I am trying to purge users - but unfortunately all users from LDAP - is also within the list of users it wants to try to remove.. I wanted to only remove local users :(
if I could do : unless { [ 'ldapusers', 'in', 'groups'] } - I could filter them out (as long as I ensure they're all in that group in ldap).
It would be nice if the puppet ldap resource provider could show the backend for each user.. but :(