Why is there a isNullOrEmpty for Array<Int> ...

# stdlib

[nkiesel]

Why is there a isNullOrEmpty for Array<Int> but not for IntArray in stdlib?

[Joffrey]

I honestly don't know, but the question IMO should be why is there this function at all? Not sure how useful it can be. Using a nullable collection usually implies that you care about the difference between null and empty, so why use this function at all?

[nkiesel]

This comes up often when dealing with Java APIs which are out of control

[Joffrey]

But then you just call the java API and use ?: emptyList() , basically dealing with java issues at the java boundary. It's good practice to get rid of platform types quickly, so we might as well deal with null there

[nkiesel]

I get a Java class which has 3 such lists or arrays. For most of them, I can use if (!j.a.isNullOrEmpty()) process(j.a) without having to create empty collections. But does not work for IntArray or BooleanArray

[nkiesel]

But really, stdlib should be consistent. This method exists for most collections, but not for IntArray or BooleanArray. And to these should per my understanding be just slightly more efficient implementations of Array<Int> or Array<Boolean>, so I would expect the same set of convenience methods

[Joffrey]

Yes I agree with the consistency argument. My point was that we should get rid of those entirely to make it consistent rather than add the missing ones.

[Joffrey]

Now for your specific case, if you really need those you can very easily write your own, or just use array == null || array.isEmpty()

[nkiesel]

Of course I could (and did) work around this limitation

[nkiesel]

And of course removing established methods from stdlib is a very long winded and expensive process

[ephemient]

array?.isEmpty() != false

[nkiesel]

Yeah, used array?.isEmpty() == true, but still surprised by the inconsistency

[ephemient]

== true means null → false, which isn't what isNullOrEmpty() does

[nkiesel]

Right, I just looked at my code and I actually do have != false. Thanks

[Joffrey]

And that is why using array == null in a separate condition is probably better. Shorter is not necessarily more readable.

[ephemient]

I think != false reads perfectly fine. == null || doesn't work for more complex expressions (without binding a name specifically for it)