Intersection and Union Types for Java

[Suminda Sirinath Salpitikorala Dharmasena]

Hello,

Can the Java type system be extended to accommodate Intersection and Union
Types.

Currently we can write:
   <T extends A & B> void f(T t) { ... }

but not

   <T extends A | B> void f(T t) { ... }

or

   <T extends (A | B) & C> void f(T t) { ... }

Also we cannot have

   void f(A & B t) { ... }

or

   void f((A | B) & C t) { ... }

When considering languages like Ceylon (https://ceylon-lang.org/) and Scala
3 / Dotty (https://dotty.epfl.ch/) these seem to be very useful.

Suminda
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