Alter method signature for child class in Typescript?

Question

In the example below (Typescript, 1.7+), what would I have to change to allow B.callback to have a different signature than A.callback?

class A {
    callback(result: number) {
    }
}


class B extends A {
    callback(result: number, option: number) {
    }
}

Currently this gives test.ts(7,7): error TS2415: Class 'B' incorrectly extends base class 'A'.

In the real world my example is more complex, but I can dynamically (more or less) guarantee (based on some configuration) that the requested parameters will be there.

Answer 1

Depending on the situation, the following solution may suffice too:

class A {
    callback(result: number) {
    }
}


class B extends A {
    callback(result: number, option?: number) { // make 'option' optional
    }
}