CCGraph.Lazy_tree
type ('v, 'e) t = {
vertex : 'v;
children : ('e * ( 'v, 'e ) t) list Stdlib.Lazy.t;
}
val map_v : ( 'a -> 'b ) -> ( 'a, 'e ) t -> ( 'b, 'e ) t
val fold_v : ( 'acc -> 'v -> 'acc ) -> 'acc -> ( 'v, _ ) t -> 'acc