recursive map specification

[mario.blunk.gplus@gmail.com]

Hello,

I want to specify a recursive map. To simplify the problem I use the example of a person and its ancestors and ancestors ... The problem does not seem special but I haven't found a solution. The approach below does not compile:

type person is record
 name : unbounded_string;
end record;

package tree is new ordered_maps 
 (
 key_type => person,
 element_type => tree.map -- compiler error. "tree" undefined
 );

Any ideas ? Thanks a lot !