Question about Kotlin vs Java generics: this compiles just fine in Kotlin ```open class Animal<T...

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[poohbar]

Question about Kotlin vs Java generics:

this compiles just fine in Kotlin

open class Animal<T1, T2>

class Cat<I> : Animal<I, List<I>>()

val x: Animal<String, List<String>> = Cat()

however trying to do the same instantiation in java fails:

Animal<String, List<String>> x = new Cat<String>() // error

Is there something I can do to improve the generics in the Kotlin code so that they can be used from Java just like from Kotlin?

[ephemient]

class Cat<I> : Animal<I, List<@JvmSuppressWildcards I>>()

[poohbar]

that fixed it! thanks… just not sure why is it needed..

declaring the same 2 classes in Java works in both Java and Kotlin 🤔

[ephemient]

because Kotlin's List is declared with an out type parameter, the translation to Java is normally List<? extends String>. this is more general than a Java List<String> (well, not for String in particular because it's final, but the typechecker doesn't know that)