proposition: Lemma DN_fmap {A: Type}: DN A -> forall B, (A -> B) -> DN B.
proof: Proof. firstorder. Qed.
imports: CoRN.algebra.RSetoid CoRN.metric2.Metric CoRN.metric2.UniformContinuity CoRN.model.totalorder.QposMinMax Coq.Classes.Morphisms