How can you convert an interface to a specific type if all available types have identical methods?

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If all available types have identical methods, then you can simply cast the interface to the desired type like this:

interface MyInterface {
  doSomething(): void;
}

class MyClass implements MyInterface {
  doSomething() {
    console.log("Doing something");
  }
}

const myInstance: MyInterface = new MyClass();

const myInstanceAsClass = myInstance as MyClass;

In the above example, we have an interface MyInterface and a class MyClass that implements it. We create an instance of MyClass and cast it to MyInterface. Then, we cast myInstance back to MyClass using the as keyword. Since both MyClass and MyInterface have identical methods, this works without any issues.