Function overloading in Javascript - Best practices

Question

What is the best way(s) to fake function overloading in Javascript?

I know it is not possible to overload functions in Javascript as in other languages. If I neede

Answer 1

For your use case, this is how I would tackle it with ES6 (since it's already the end of 2017):

const foo = (x, y, z) => {
  if (y && z) {
    // Do your foo(x, y, z); functionality
    return output;
  }
  // Do your foo(x); functionality
  return output;
}

You can obviously adapt this to work with any amount of parameters and just change your conditional statements accordingly.