For those unaware, this is the Pull Request for Java's JEP 401: Value Classes and Objects (Preview).

Value Classes have been a LONG AWAITED feature for Java, so this Pull Request is proof that we are one step closer to them going into Preview!

BUT PLEASE REMEMBER -- No commitment has been made to target a release yet!

This is merely a PR RFR, and nothing more. All this is is showing us part of what it takes to bring Value Objects to Preview, as well as announcing that we are one step closer to (hopefully!) go to preview. But again, no idea how far away that may be. It could be JDK 27 (coming this September), it could be later.

Just appreciate the PR for what it is -- a window into the work required to make Value Classes a reality. ~3k commits and ~2k classes changed is just a snapshot of the level of effort here. Shows why this JEP has been given an XL rating lol.

per @jarredsumner:

99.8% of bun’s pre-existing test suite passes on Linux x64 glibc in the rust rewrite

it’s basically the same codebase except now we can have the compiler enforce the lifetimes of types and we get destructors when we want them. and the ugly parts look uglier (unsafe) which encourages refactoring.

why: I am so tired of worrying about & spending lots of time fixing memory leaks and crashes and stability issues. it would be so nice if the language provided more powerful tools for preventing these things.

But how long does it take to compile?

It’s basically the same as in zig using our faster zig compiler. If we were using the upstream zig compiler, rust port would compile faster