n-params vs single param - Carlos Menezes

When writing functions in TypeScript (and, truthfully, any language that does not support named parameters), you either pass arguments individually (n params) or group them into a single object. While both are valid, I am yet to find a case were object parameters aren't the better choice.

Say you call a function which creates a user:

const signup = () => {
  // ...
  createUser("John", "Doe", 28, true);
  // ...
};

At a glance, can you tell what each value means? You’re left guessing: what’s 28? What’s true? The more parameters you add, the more brittle and confusing this becomes.

Instead, consider using an object parameter:

type TCreateUserInput = {
  firstName: string;
  lastName: string;
  age: number;
  isActive: boolean;
};

const signup = () => {
  // ...
  createUser({ firstName: "John", lastName: "Doe", age: 28, isActive: true });
  // ...
};

No guessing. No worrying about the order. Your code is self-documenting. Plus, TypeScript gives you full autocompletion and type safety.

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Apr 17, 2025	n-params vs single param