anchor.diff:      grants_xml(Grantees, []).
   
   %% @doc Assemble the xml for the set of grantees for an acl.
  --spec grants_xml([acl_grant()], []) -> term().
  +-spec grants_xml([acl_grant()], list()) -> list().
   grants_xml([], Acc) ->
       lists:flatten(Acc);
   grants_xml([HeadGrantee | RestGrantees], Acc) ->
  
positive.code:             Grant = process_grant(Content, {{"", ""}, []}, RiakPid),
              UpdAcl = Acl?ACL{grants=add_grant(Grant, Acl?ACL.grants)};
          _ ->
              lager:debug("Encountered unexpected grants element: ~p", [ElementName]),
              UpdAcl = Acl
      end,
      process_grants(RestElements, UpdAcl, RiakPid).
  
negative.code:         {ok, {User, _}} ->
              User?MOSS_USER.canonical_id;
          {error, Reason} ->
              _ = lager:warning("Failed to retrieve canonical id for ~p. Reason: ~p", [Email, Reason]),
              []
      end.
  
  