I wonder why `class` only implies `final` but `override` only implies `open`? Should "overridability...

# getting-started

[Loney Chou]

I wonder why class only implies final but override only implies open? Should "overridability" be `open`'s at all? I remember this is the only place where final is used.

class A // final

interface B {
    fun foo()
}

class C : B {
    override fun foo() // final
}

open class D : B {
    override fun foo() // OPEN
}

if it's final by default then D.foo should also just finalize overridability UNLESS you mark it open. Having both open and final is so inconsistent.