kotlin_reified.kt

// 参考: https://qiita.com/takusemba/items/f05ff78b39d40937901f
inline fun <reified T> List<T>.filterInstance(): List<T> {
    val destination = mutableListOf<T>()
    this.forEach {
        //これはできない
        //println(it::class)
        if (it is T) destination.add(it)
    }
    return destination
}

fun main(args: Array<String>) {
    // Your code here!
    val nums = listOf(1, 2f, 3, 4f, "5", Pair(6, '6'), null)
    val ints = nums.filterIsInstance<Number>() // [1, 3]
    println(nums)
    println(ints)
    println(listOf(1, 2f, 3, 4f, "5", Pair(6, '6'), null).filterIsInstance<Int>())
}