message: using const instead of var
diff: @@ -11,8 +11,8 @@ describe("Pow", () => {
  it("can do powers of 2", () => {
  return ConstantOutput(() => {
  - var signal = new Signal(0.3);
  - var pow = new Pow(2);
  + const signal = new Signal(0.3);
  + const pow = new Pow(2);
  signal.connect(pow);
  pow.toDestination();
  }, 0.09);
  @@ -20,8 +20,8 @@ describe("Pow", () => {
  it("can compute negative values and powers less than 1", () => {
  return ConstantOutput(() => {
  - var signal = new Signal(-0.49);
  - var pow = new Pow(0.5);
  + const signal = new Signal(-0.49);
  + const pow = new Pow(0.5);
  signal.connect(pow);
  pow.toDestination();
  }, 0.7);
  @@ -29,8 +29,8 @@ describe("Pow", () => {
  it("can set a new exponent", () => {
  return ConstantOutput(() => {
  - var signal = new Signal(0.5);
  - var pow = new Pow(1);
  + const signal = new Signal(0.5);
  + const pow = new Pow(1);
  pow.value = 3;
  signal.connect(pow);
  pow.toDestination();
  