[Vala] valasemanticanalyzer error

[Martin DeMello <martindemello gmail com>]

What do I need to do to get the following code to compile? It dies with

$ valac --pkg gee-1.0 test.vala
**
ERROR:valasemanticanalyzer.c:2948:vala_semantic_analyzer_get_actual_type:
assertion failed: (instance_type != NULL)
Aborted


# -------------------------------------------------------
using Gee;

public interface Enumerable<G, T> : Iterable {

        public delegate T DFunc(G elem);

        public void map(DFunc fn, Gee.List<T> acc) {
                foreach (G i in this) {
                        acc.add(fn(i));
                }
        }
}

public class EnumerableList<G, T> : Gee.ArrayList<G>, Enumerable<G, T> {
}

public static int main(string[] args) {
        var a = new EnumerableList<int, string> ();
        a.add(1);
        a.add(2);
        a.add(3);
        var b = new Gee.ArrayList<string> ();
        a.map( (i) => { return "%d".printf(i); }, b);
        foreach (string i in b) {
                println(i);
        }

        return 0;
}

#----------------------------------------------------


martin