fun <T> MutableCollection<in T>.addAll(
    elements: Iterable<T>
): Boolean

Adds all elements of the given elements collection to this MutableCollection.

fun <T> MutableCollection<in T>.addAll(
    elements: Sequence<T>
): Boolean

Adds all elements of the given elements sequence to this MutableCollection.

fun <T> MutableCollection<in T>.addAll(
    elements: Array<out T>
): Boolean

Adds all elements of the given elements array to this MutableCollection.