prelude inductive nat : Type | zero : nat | succ : nat → nat namespace nat end nat open nat inductive {u} list (A : Type u) : Type u | nil {} : list | cons : A → list → list namespace list end list open list check nil check nil.{0} check @nil.{0} nat check @nil nat check cons zero nil inductive {u} vector (A : Type u) : nat → Type u | vnil {} : vector zero | vcons : forall {n : nat}, A → vector n → vector (succ n) namespace vector end vector open vector check vcons zero vnil constant n : nat check vcons n vnil check vector.rec