A modern programming language that makes developers happier.

kotlinlang

What are the main highlights of this release?

Not much tbh. A lot of features have been put on hold until FIR is complete.

I saw that kotlin now has intersection types, with the very specific `T &amp; any`. However, it's supported in the parser and in the compiler internally so it should be fairly simple to just lift that restriction...

Are the Intersection types equivalent to Union types?

No, they are a different concept. They are 'the opposite' in some way.

If A and B are groups, then
 A | B contains all elements that exist in A *or* B
 A &amp; B contains all elements than exist in A *and* B

So, `String | Int` is all Strings and ints, but `String &amp; Int` is `Nothing` because nothing is both a String and an Int.
`Comparable | Closeable` is any object that is comparable or closeable, `Comparable &amp; Closeable` is any object that is comparable AND closeable.
`T | any` : if T is nullable, then any non-nullable object, or a nullable instance of T. If T is not nullable, then it's equivalent to `any`.
`T &amp; any` : if T is nullable, then any non-nullable instance of T. If T is not nullable, then it's equivalent to `T`.