Project 18: Registration Flow

JS Wizard

Builds on these lessons

Module Pattern Factory Pattern Singleton Pattern Modular Modules

Step 1 of 3

Project

The Module Pattern

Wrap validation logic in an immediately-invoked function expression that returns just the public pieces you want exposed, keeping an internal errorCount variable private. The module pattern is how JS achieved "private" state and a clean public API before native modules existed.

🎯 Your Task

Please add the exact code shown in the light gray box below to your editor.Do not delete your previous code, just insert these new lines in the correct place!

const FormValidator = (function () {
  let errorCount = 0;

  function validateEmail(email) {
    const isValid = email.includes("@");
    if (!isValid) errorCount += 1;
    return isValid;
  }

  return { validateEmail };
})();

console.log(FormValidator.validateEmail("not-an-email"));
console.log(FormValidator.validateEmail("jordan@example.com"));

← Previous Next →