End FindLemmas.
(* if maps store units, i.e., we keep them just for sets *)
(* then we can simplify the find_eta lemma a bit *)

(* Specifications: *)
Lemma domeq_eta (K : ordType) (U : union_map_class K unit) (f1 f2 : U) :
dom_eq f1 f2 -> f1 = f2.