``` sealed class Foo { class A : Foo() cla...

# announcements

[kirillrakhman]

sealed class Foo {
    class A : Foo()
    class B : Foo()
    data class C(val s: String) : Foo()

    override fun equals(other: Any?) = other != null && other.javaClass == javaClass
    override fun hashCode() = javaClass.hashCode()
    override fun toString() = javaClass.simpleName
}