fact: Definition bindLazyListPf {A B : Type} (l : LazyList A) (f : forall (x : A), In_ll x l -> LazyList B) : LazyList B := (concatLazyList (mapLazyListProof l f)).
imports: ExtLib.Structures(Functor Applicative) List QuickChick(Tactics) Coq(ssreflect)