cogent VS koka

Cogent, late 2010s, a language with linear types for verification. The idea is that you write functional-looking code that is easy to verify using the functional semantics, but with an efficient compilation strategy enabled by linear types to get realistic system programs.

Of course. Here was the first incarnation: https://github.com/amw-zero/sligh. It has a decent overview of the idea in the readme. To sum it up here, the idea is: have a language built around model-driven development and model-based testing, where you write a simple model of an application, and the implementation and model-based tests are compiled for you. I wrote about the overall model-based testing strategy here. This idea comes from self-certifying compilers that produce proofs of their correctness such as Cogent, but we drop the formality requirement and use property-based testing to compare the implementation and model.

That made me think of this project Cogent. This is almost certainly not what you’re looking for, because it’s aimed at formal verification. But, it does have some interesting properties, like manual memory management through uniqueness types. It doesn’t even support recursion though so, probably not so good as a general purpose PL.

https://github.com/NICTA/cogent is for auto generating isabelle theorems + C code.

This post by the Koka-author is an update about what's currently being worked on: https://github.com/koka-lang/koka/discussions/339

Some programming language like JS, use path-based imports, that's not good for making a stabel API.

See https://api-extractor.com/pages/setup/configure_rollup/#:~:text=(The%20API%20Extractor,with%20that%20effort.)

And https://github.com/koka-lang/koka/issues/31#issuecomment-1482200826

It also offers a great Inversion of Control mechanism where everything is customisable, and, unlike Capability Objects, AESs also offer compatibility with type inference (you can pass functions doing IO to map, and it Just Works(TM)) and first-class control over stack frames (because really a continuation function is just some stack frames, which you can manually move to the heap if you want a closure; which means async is an effect!). It also is composable in ways Monads are not.

Koka and other languages implementing Algebraic Effect Systems make everything a user-defined case of coroutines: async is just another effect/Monadic type. Zig does something similar by having first class stack frames, making all function calls possibly asynchronous.

Super interesting, there is a proposal to add this to JavaScript and several languages that use this, unison, koka & eff. I had no idea this was even a thing!

Koka, already cited in this thread, early 2010s. Koka's first claim to fame was a usable effect system (at the type were, basically, effect systems were not usable in practice; in fact few languages have managed to do as well as Koka since). Now its author is working on cool implementation strategies for functional languages as well.

I'm a software engineer with 3 years of professional experience. I worked for 2 years at Microsoft on Azure Compute and now work at Google, working on improving Google search. I am the sole maintainer of the popular open-source library microlens with 80k downloads. I've also contributed to the Koka programming language developed at Microsoft Research.

By implementing all of those optimizations in the Koka programming language, they achieved GC overhead much less and execution time faster than the other languages including OCaml, Haskell, and even C++ in several algorithms and data structures that frequently keep common sub-structures of them, such as red-black trees. For more information, see the latest version of the paper.