fact: Fixpoint filter_LazyList {A} (p : A -> bool) (l : LazyList A) := match l with | lnil => lnil | lcons h t => if p h then lcons h (fun tt => filter_LazyList p (t tt)) else filter_LazyList p (t tt) end.
imports: ExtLib.Structures(Functor Applicative) List QuickChick(Tactics) Coq(ssreflect)