compiler/testData/psi/examples/array/MutableArray.kt - third_party/github/JetBrains/kotlin - Git at Google

 /**
   These declarations are "shallow" in the sense that they are not really compiled, only the type-checker uses them
 */

 open class ReadOnlyArray<out T> : ISized {
   @[operator] fun get(index : Int) : T
 }

 open class WriteOnlyArray<in T> : ISized { // This is needed to keep IIterator's <T> covariant
   @[operator] fun set(index : Int, value : T)
 }

 class MutableArray<T> : ReadOnlyArray<T>, WriteOnlyArray<T> {/*...*/}
	/**
	These declarations are "shallow" in the sense that they are not really compiled, only the type-checker uses them
	*/

	open class ReadOnlyArray<out T> : ISized {
	@[operator] fun get(index : Int) : T
	}

	open class WriteOnlyArray<in T> : ISized { // This is needed to keep IIterator's <T> covariant
	@[operator] fun set(index : Int, value : T)
	}

	class MutableArray<T> : ReadOnlyArray<T>, WriteOnlyArray<T> {/.../}