TS2420

error TS2420: Class ‘Dog’ incorrectly implements interface ‘Animal’. Property ‘name’ is private in type ‘Dog’ but not in type ‘Animal’.

Broken Code ❌

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interface Animal {
  name: string;
}

class Dog implements Animal {
  constructor(private name: string = 'Bobby') {}
}

Fixed Code ✔️

The Animal interface defines a public name member. The name property in our Dog class must therefore also be public:

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interface Animal {
  name: string;
}

class Dog implements Animal {
  constructor(public name: string = 'Bobby') {}
}

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