fun <T> mutableStateOf(
    value: T,
    policy: SnapshotMutationPolicy<T> = structuralEqualityPolicy()
): MutableState<T> = createSnapshotMutableState(value, policy)

@Stable
interface State<out T> {
    val value: T
}

@Stable
interface MutableState<T> : State<T> {
    override var value: T
    operator fun component1(): T
    operator fun component2(): (T) -> Unit
}

        var _compose = mutableStateOf(0)		// 監視対象（_compse）の変数

        setContent {
            MyApplicationTheme {
                Surface(
                    modifier = Modifier.fillMaxSize(),
                    color = MaterialTheme.colorScheme.background
                ) {
                    Text(text = "Compose count = %3d".format(_compose.value))
					//                                     ↑↑監視対象の参照↑↑
					// 定期的なComposeが行われる
					//
                }
            }
        }

        // 別スレッドでアプリの状態を更新
        lifecycleScope.launch(Dispatchers.Default) {
            repeat(100) { delay(5000); _compose.value++ }  // 5秒間隔
        }