开心愉快的使用 kotlin function

let

`fun main(args:Array<String>){
val person = Person()
println(person.toString())

person.let {
it.name = "Peter"
it.age = 20
}

println(person.toString())

}

data class Person(var name: String ="", var age:Int = 0)`

with

val p1 = with(Person()) { name = "zhangsan" age = 20 return@with this }

apply

val p2 = Person().apply { name = "lisi" age = 25 }

also

use

takeif

takeUnless

measureTimeMillis