Use Switch for Pattern Matching

Instead of complicated if/else if/else, use switch instead for better readability.¹

const howSoon = (days) => {
  switch (true) {
    case days <= 7:
      return 'soon';
    case days > 7 && days < 30:
      return 'kind-of-soon';
    case days >= 30:
      return 'not-soon';
    default:
      return;
  }
};

Pattern Matching in JavaScript ↩