ante VS sixten

Have you had a look at Ante? It looks a lot like a Rust 2.0 with better ergonomics. There are a lot of interesting ideas.

Ante is what you are looking for. It's an ML descendant with no RTS nor AGC.

In my experience, people believe that programming languages are a solved space, and we should stick with what we have.

It's unfortunate; because languages are very polarized today. I think there's a lot of room for languages that are safe, fast, and most importantly, *easy.* Today's languages are generally two out of three.

Luckily, a lot of languages are exploring that space!

* Vale is blending generational references with regions, to have memory-safe single ownership without garbage collection or a borrow checker. [0]

* Cone is adding a borrow checker on top of GC, RC, single ownership, and even custom user allocators. [1]

* Lobster found a way to add borrow-checker-like static analysis to reference counting. [2]

* HVM is using borrowing and cloning under the hood to make pure functional programming ridiculously fast. [3]

* Ante is using lifetime inference and algebraic effects to make programs faster and more flexible. [4]

* D is adding a borrow checker!

[0] https://verdagon.dev/blog/zero-cost-refs-regions

[1] https://cone.jondgoodwin.com/

[2] https://www.strlen.com/lobster/

[3] https://github.com/Kindelia/HVM

[4] https://antelang.org/

[Ante](https://antelang.org/): lifetime inference, refinement types, algebraic effects.

Immutable data structures don't necessarily require more memory: they can avoid deep copies. They are also automatically thread safe without expensive (slow) locking mechanisms. They also don't necessarily reduce cache locality. The reduced cache locality in the case of Haskell (I think) mainly comes from the representation of objects in its implementation (improved STG) which uses extensive boxing and jumps that hinder both spatial and temporal locality (require review/comment from GHC/Computer Architecture experts, take it with a grain of salt). Objects can be much more efficiently represented if not for the need to implement lazy (call-by-need) semantics. See sixten and futhark for examples.

[Sixten](https://github.com/ollef/sixten): functional programming with unboxed data by default.

I can't answer this well and don't know of any resources, but I have seen it before in the parser for sixten:

    https://github.com/ollef/sixten/blob/60d46eee20abd62599badea85774a9365c81af45/src/Frontend/Parse.hs#L458

Sixten is a language that allows precise control over memory layout of algebraic data types.

For something more peripherally related, check out Sixten. Its focus is on using unboxed value representations, which is in spirit close to what you are proposing, and some of its ideas might be good inspiration.