-- implicit builtin bool
-- Builtin nat requires builtin bool when translated to integers, because
-- matching is translated to comparison operators and cases on booleans.
module test045;

builtin nat
type Nat :=
  | zero : Nat
  | suc : Nat → Nat;

syntax fixity additive := binary {assoc := left};

syntax operator + additive;

+ : Nat → Nat → Nat
  | zero b := b
  | (suc a) b := suc (a + b);

main : Nat := suc zero + suc (suc (suc zero));