A modern programming language that makes developers happier.

kotlinlang

Hi! When I extend a Java method that has `String[]` in signature Kotlin recommends to have it as `Array&lt;out String&gt;`. It is literally useless because `String` is `final` in Java.

You cant change the value of a string, but you can change an array element to contain a different string. In general an array is not a great choice for a parameter type.

That's not relevant though. You're right that it's a useless suggestion, but for general types it's a good idea.

It's a good idea because it makes it so you can't set values on the array. It makes you explicit about the purpose if the parameter. That's why type of `vararg a: String` is also `Array&lt;out String&gt;`

I am not sure if compiler will allow setting indices considering String is final. Therefore it isn't useless.

I agree, but a pedantic note: the mutability argument is only half, true, stuff like `reverse()` still works.

There's a bit of confusion here. String is final. All good. But String[] allows you to change any index of it to another String. final String[] a = .... ; a[5] = "hello" is perfectly valid. a = .... is not.