[Someone]

Java compilers are getting more and more advanced, but I don’t think they will ever become the magical “sufficiently advanced compiler” that produces code that’s as good as humans _could_ (but often won’t, because of time constraints) write.

I don’t think anybody fully disagrees with that. At least, I haven’t heard people claim int can be removed from the language because a good compiler can produce identical code for Integers.

And yes, that can also apply to instances that do escape. A sufficiently advanced compiler could in some/many cases figure out that an array of Integer can be compiled down to an array of int. However, it’s way easier for a compiler to check a programmer’s claim “we won’t use features of Integer on these ints” than to deduce that code won’t, so a little bit of programmer effort allows for a simpler compiler that can produce faster code.

For me, records and (future) value types are examples of such “little bits of programmer effort”

[eklavya]

I could be wrong but I don’t think dart has ints, I think it only has objects.

[Someone]

https://api.dart.dev/stable/2.6.0/dart-core/int-class.html:

“Classes cannot extend, implement, or mix in int.”

https://api.dart.dev/stable/2.6.0/dart-core/num-class.html:

“It is a compile-time error for any type other than int or double to attempt to extend or implement num.”

⇒ it seems that, technically, you’re right. int is an object in Dart. At the same time, it’s a restricted type of object.

So restricted that I think it is aan object only in name/at compile time.