typeOf.lean:11:22-11:25: error(lean.synthInstanceFailed): failed to synthesize instance of type class
  HAdd Nat Nat Bool

Hint: Type class instance resolution failures can be inspected with the `set_option trace.Meta.synthInstance true` command.
typeOf.lean:12:0-12:5: error(lean.synthInstanceFailed): failed to synthesize instance of type class
  HAdd Bool Nat Nat

Hint: Type class instance resolution failures can be inspected with the `set_option trace.Meta.synthInstance true` command.
typeOf.lean:20:56-20:62: error: invalid reassignment, term has type
  Bool
but is expected to have type
  Nat
typeOf.lean:29:55-29:59: error: natural number expected, value has type
  Bool
but is expected to have type
  Nat