TS2531

error TS2531: Object is possibly ‘null’.

Broken Code ❌

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type Person = {
  address: {
    street: string;
    zipCode: number;
  } | null;
  name: string;
};

function logStreet(person: Person): void {
  console.log(person.address.street);
}

Fixed Code ✔️

The error originates from the fact that address can be null. To fix the problem, we can check if address is null by using optional chaining:

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type Person = {
  address: {
    street: string;
    zipCode: number;
  } | null;
  name: string;
};

function logStreet(person: Person): void {
  console.log(person.address?.street);
}