how to write a function if I don't know number of parametrs (JS, Node.js)

Question

I want to write a function which returns me formatted string. I wrote a random function "pickRandom" do I get always one random string from the array.

My example data:

const arr = ['Hi %s', '%s nice to seee you'];

For this example is easy to write a function:

const randomOutput = (arrayToChange, variable) => {
  const randomString = pickRandom(arrayToChange);

  return util.format(randomString, variable);
};

but how to modify my function that it works with multiple and no parametrs too. Is it possible? One function for every case?

I would like that it works:

const arr = ['Hi %s', '%s nice to seee you'];
const arr = ['Hi', 'Hi you'];
const moreP= ['Hi %s, you are %d years old', '%s, your age %d'];

So in that case it wont work:

randomOutput(moreP, "Anna", 19);

Answer 1

You could use arguments spread syntax

const randomOutput = (arrayToChange, ...variables) => {
  const randomString = pickRandom(arrayToChange);

  return util.format(randomString, ...variables);
}