decl test_lambdas : Unit -> Unit
def test_lambdas = {
  const lambda1 = \x -> x * x
  // const lambda2 = \(x : #Hash) -> x.hash // ??
  const lambda3 = \x y -> x + y

  // TODO: type LambdaType = Int -> Int // ?? type keyword ??
  // const typed_lambda = \x -> x + 1

  const lambda4 = \x -> {
    ; IO.print x
    const y = x + x
    return y
  }
}