Type.Family.Nat
data N
type family NatEq x y :: Bool
type family Iota x :: [N]
type family Pred x :: N
type family x + y :: N
type family x * y :: N
type family x ^ y :: N
type N0
type N1
type N2
type N3
type N4
type N5
type N6
type N7
type N8
type N9
type N10
type family a == b :: Bool