``` interface A fun doIt Long class B A override fun doIt Lo kotlinlang #announcements

``` interface A { fun doIt(): Long? } class B...

rrader

05/02/2018, 7:28 AM

Copy code

interface A {
    fun doIt(): Long?
}

class B : A {
    override fun doIt(): Long {
        return 42
    }
}

Why it is correct to implement and change the signature?