I'm using this in my command store in order to register the command listeners

There are some added debug messages which will help explain my next screenshot

Result

As you can see in the console, it only finds my onDisable method which is from my Module class which I inherit in Command Store

But, if I uncomment that line in onEnable, it'll find all the functions

does Kotlin support some kind of "where T is not X" generic functionality? or is this likely only achievable by lint?

Maybe you can make a second function with the "not" signature and deprecate it?

Be careful though, it doesn't really work with the rest of the type system:

val x = "hello"
val y: Any = "hello"
noString(x) //you want to disallow this
noString(y) //but this will always be possible

You still can't be sure that

noString

won't be called with a String parameter.

noString(x as Any)

works

you can use an overload anyway

But not instance of is a hard contraint to check also. You would have to restrict it to final classes to get a compiletime guarantee

if you want people to be alert

actually compile time and runtime checks are two things

compile time, as mentioned above, is overridden as easily as

as Any

Actually, you could similarly overcome any other type checks using

as

, e.g.

System.exit("abc" as Any as Int)

, but that'd obviously trigger a ClassCastException

so as an API developer, you don't need to be a cybersecurity expert and try to block every hole

just making sure it's obvious it doesn't work is enough

actually iirc the same practice is being used in ktor

script {+"Code"}

"abc" as Any as Int

doesn't do anything, it's not a "workaround" it doesn't even start calling the function.

have you looked at Kotlin contracts?

Is there a reason why smart-casting to a

Cat

is not possible in these two (similar) cases? This is mainly out of curiosity, as I was explaining sealed classes to a colleague and kind of expected this to work.

I filed an issue about this a couple of years ago: https://youtrack.jetbrains.com/issue/KT-18950

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