With the new model, the reference `M.Foo` doesn't resolve but `M.t.Foo` does. ```ocaml module M : sig type t = Foo end (** {!constructor:M.Foo} {!constructor:M.t.Foo} *) ``` In `Paths_types`, constructor parent should be `parent` or a new `constructor_parent` instead of `datatype`. Also, the type for references allows extension and exception constructors in `{!constructor:..}` references but won't resolve them.