class b, c, d, e, f, g
class Type < Type
class Type
class Type < Type
class d < a
class a < d
class a < a
class a < b
class b < d
class d < d
class d < a
type t:a
class h < a
class h < c
type a__b, [__] : a -> b
var x : a; y : Type; x : y
var x : s
var x: b
var x < t
type a __ : b