structural type Foo0 = Foo0
structural type Foo1 a = Foo1 a
structural type Foo2 a b = Foo2 a b
structural type Foo3 a b c = Foo3 a b c
structural type List a = Nil | Cons a (List a)

use Foo0 Foo0
use Foo1 Foo1
use Foo2 Foo2

x = match Foo0 with
  Foo0 -> 1

y = match Foo1 1 with
  Foo1 1 -> 0
  Foo1 _ -> 10

z = match Foo2 1 "hi" with
  Foo2 1 _ -> 1
  Foo2 x _ -> x

w = match Foo3.Foo3 1 2 "bye" with
  Foo3.Foo3 1 2 x -> x Text.++ "bye"
  _ -> ""

w2 = cases
  Foo3.Foo3 1 4 x -> x Text.++ "bye"
  Foo3.Foo3 x y z -> z Text.++ z

len : List a -> Nat
len = cases
  List.Nil -> 0
  List.Cons _ t -> len t + 1

foo = cases
  List.Cons h t 
    | h > 10 ->
      x = 3124
      y = 230
      x + y
    | h < 10 -> 10
    | otherwise -> 11

  List.Nil -> 0

foo2 = cases
  List.Cons h t | h > 10 -> 1
                | h < 10 -> 2
                | otherwise -> 3
  List.Nil -> 0

> (w, w2 (Foo3 1 4 "bye"), len (List.Cons 1 List.Nil), foo (List.Cons 0 List.Nil), foo2 List.Nil)