Kotlin Nothing

Maybe you are very unfamiliar with him, so look at such a piece of code

Oriented TODO ()

How will it work?

Running the above code is fine.

But the following code gives an error

package com.anguomob.learn
const val number=1001;
fun main() {
    when(number){
        1-> TODO();
        1001-> TODO();

    }
}

Error content

Exception in thread "main" kotlin.NotImplementedError: An operation is not implemented.
	at com.anguomob.learn.LearnKTKt.main(LearnKT.kt:6)
	at com.anguomob.learn.LearnKTKt.main(LearnKT.kt)

In fact, TODO is a type of Nothing

 

Of course not only todo

There are also things like exitProcess

 They all have to throw an exception to exit, so this is used