The singleton pattern

intresting.js

const SingletonPattern = (() => {
  let instantiated;
  let init = () => {
    // singleton
    return {
      publicMethod: () => {
        console.log("hello world");
      },
      publicProperty: "test"
    };
  };

  return {
    getInstance: () => {
      if (!instantiated) {
        instantiated = init();
      }
      return instantiated;
    }
  };
})();