关于Kotlin "===" 的特性

后续补充

code：

var x1: Int? = 127var x2: Int? = 127println("x1 === x2 : ${x1 === x2}")var z1: Int? = 128var z2: Int? = 128println("z1 === z2 : ${z1 === z2}")// 输出x1 === x2 : truez1 === z2 : false