@thana I submitted a feature request for allowing to explicitly request use of

contentEquals

a while ago: https://youtrack.jetbrains.com/issue/KT-26499 You can add your vote.

I always wanted to ask what’s the use-case of storing arrays in data classes? Where does it come up?

I can't recall if `inline class`es can do this, but this kind of thing is useful in other languages when you want type-level validation:

data class NonEmptyList<T>(val values: List<T>)

then you throw in

init

if the list is empty. That's the use case that comes to mind for me anyway

@basher but you are storing

List

, not

Array

🙂

@elizarov in my case i need to satisfy a javascript interface which requires an array here and not a list

Ah, I see. Inline classes would help here when they are really supported by JS backend.

@Pavlo Liapota fair point! Same idea though?

The issue is with arrays only.

equals()

of a

List

compares elements and

toString()

shows elements, but it does not like that for arrays.

arrayOf(1) == arrayOf(1) // false
listOf(1) == listOf(1) // true

@elizarov Use case is for primitive arrays and unsigned number arrays, where using

List

means performance hit due to autoboxing and you don't need variable size or read-only defense.

Thanks. That makes sense.