kotlin: filterIsInstance for a subclass/instance of a sealed class

filterIsSubClassInstanceOf.kt

/**
 * Filters the elements of this list to be instances of the specified type parameter [Child].
 */
public inline fun <reified T, reified Child : T> Iterable<T>.filterIsSubClassInstanceOf(): List<Child> {
    return this.filterIsInstance<Child>()
}

// usage example ...

sealed class S {
    object A : S()
    object B : S()
    object C : S()
}

fun foo() {
    val source:List<S> =listOf(S.A, S.B, S.C)
    val outcome:List<S.A> =source.filterIsSubClassInstanceOf()
}