Kotlin中apply、let、also和run的区别

(更新中。。。)

apply和also 返回引用者本身
let和run 返回最后一行

    var str : String = "abc"

    fun testApply(){
        println("Apply")
        var str0 = str.apply {
            this.toUpperCase()
            println(this)
        }
        println(str0)
    }

    fun testAlso(){
        println("also")
        var str0 = str.also {
            it.toUpperCase()
            println(it)
        }
        println(str0)
    }

    fun testLet(){
        println("let")
        var str0 = str.let {
            it.toUpperCase()
            println(it)
            Unit
        }
        println(str0)
    }

    fun testRun(){
        println("run")
        var str0 = str.run {
            this.toUpperCase()
            this.length
            UInt
        }
        println(str0)
    }

    fun testWith(){
        println("with")
        with(str){
            str = "1111"

        }
    }