On the switch true pattern

I recently stumbled upon the switch-true pattern in JavaScript. If you don’t know it, here’s an example:

function isUserValid(user) {
  switch (true) {
    case user.age < 18:
      return false;
    case user.isGuest:
      return false;
    default:
      return true;
  }
}

It’s supposed to be an improvement over using if and early returns. Here’s the same code written in a more traditional way:

function isUserValid(user) {
  if (user.age < 18) return false;
  if (user.isGuest) return false;
  return true;
}

My 16-year-old self would have loved the switch-true pattern. Why? Because it feels hacky. You’re using the language in a way that was not intended to be used. JavaScript has many of these little quirks, like doing !!value to cast to a boolean or +value to cast to a number.

Luckily, through the years, I’ve grown and matured, and I can say I do not like this pattern. I don’t see it adding anything to the usual way of writing code and, if anything, could confuse newcomers—which is something I’m against. Nothing wrong if you like it and want to use it in your projects, but if you ask me, you’re better off sticking with good old if.