Program Instance qpUnsized (qp : QProp) : UnsizedChecker (checker qp).
Next Obligation.
rewrite !semFmapSize !semReturnSize. apply imset_eq. reflexivity.
Qed.

Lemma semCheckablePolyFunSetSize:
forall {C : Set -> Type} {H : Checkable (C nat)} (f : forall T, C T) (size: nat),
(semCheckableSize f size) <->  (semCheckableSize (f nat) size).