Why I can't assign nullable type to Any in Kotlin?
Ruxo
Can anyone please explain why doing this in Kotlin is impossible?
val x :Int? = 123
val y :Any = x
I come from .NET background where Nullable type is assignable to Object type, but how are they different?
Joffrey
Nullable types are not subtypes of Any, but they are subtypes of Any?.
Any is only a superclass of non-nullable types. This makes it possible to write code that requires a non-null instance of anything, and still benefit from the safety of the type-checker (unlike when using Java's Object).
Here is an image that can help:
The following code is a valid replacement of yours:
val x: Int? = 123
val y: Any? = x
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