How to compare inline classes? My usecase. I have...

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[prasham.h.trivedi]

How to compare inline classes?

My usecase. I have defined 5 `Int`s and an Inline class using Following.

inline class State(val state: Int)

And in my regular class I have a variable of the State using Delegates.observable.

Whenever I try to compare two states, I get : State cannot be cast to java.lang.Number

My sample comparision code looks like following.

this.state==State(1)

[robin]

this.state == State(1).state

or

State(this.state) == State(1)

should work. That's exactly the use case for inline classes, that you can't accidentally cross-assign semantically different values, so you have to make it explicit.

[prasham.h.trivedi]

State(this.state) == State(1)

Doesn’t seem to work.

My variable is

var state by Delegates.observable(State(0){
___
}

Usually state is being re-assigned.

Now at some point if I compare using

1.

state=State(0)

Or

state.state==0

Both gives ClassCastException

[robin]

This compiles fine for me:

[robin]

Anything I'm doing differently than you here?

[prasham.h.trivedi]

Compilation is not an issue here. It compiled fine for me as well.

How about output? Does your code runs without any ClassCastException?

[prasham.h.trivedi]

Also, it looks like our environment is different. I use Android Studio, and probably you are in Intellij and with Java 1.8. These are not present in my build config

[robin]

Huh, you're right, I assumed you had a compile error so I didn't try to run it. Crashes for me too.

[robin]

Having a look at the compiled code it seems to me like this is an unfortunate combination of type erasure with Delegates, and the compiler messes up boxing/unboxing at some point

[robin]

Definitely looks like a bug to me.

[orangy]

@mikhail.zarechenskiy ^^

[mikhail.zarechenskiy]

Yes, it's a bug: https://youtrack.jetbrains.com/issue/KT-27737
We'll fix it soon, sorry for the inconvenience!