Program Instance unsizedMonotonicChecker (c : Checker) `{UnsizedChecker c} : 
  SizeMonotonicChecker c.

Lemma semBindGenUsinzed2 {A} (gen : G A) (f : A -> Checker) `{forall a, UnsizedChecker (f a)} : (semChecker (bindGen gen f) <-> forall a, semGen gen a -> semChecker (f a)).