dex-lang VS ghc-proposals

A really nice approach to this I've seen recently is Google's research on [Dex](https://github.com/google-research/dex-lang).

Dex

Have you tried Dex? https://github.com/google-research/dex-lang It is in a relatively early stage, but it is exploring some interesting parts of the design space.

I think [Dex](https://github.com/google-research/dex-lang) might be along the lines of what you're looking for, although its focus is on SIMD GPU-style parallelism rather than thread-level parallelism.

Dex proves indexing correctness without a full dependent type system, including loops.

See: https://github.com/google-research/dex-lang/pull/969

In case you want to see one research direction that's combining practical machine learning and functional programming, one of the authors of JAX (and the main author of its predecessor, Autograd) is writing Dex (https://github.com/google-research/dex-lang), a functional language for array processing. The compiler itself is written in Haskell. JAX is one of the most popular libraries for doing a lot of machine learning these days, along with Tensorflow and PyTorch. You might also want to see the bug in the JAX repo about adding Haskell support, for some context: https://github.com/google/jax/issues/185

This is really just a matter of how much syntax sugar you want to implement. Idris has this already, and there’s a proposal to add it to Haskell too [0]. But none of this changes the core properties of the system which make it monadic.

[0] https://github.com/ghc-proposals/ghc-proposals/issues/527

> I think Haskell needs a way to graduate (or retire) language extensions

https://github.com/ghc-proposals/ghc-proposals/pull/601

Additionally, while this proposal is focused on the simple implementation and so in the current proposal or patterns do not bind any variables as per #522, if we do get settled on syntax and then later wish to expand to allow binding variables as in #43, then the syntax is again clean and discoverable.

Yeah, a relatively natural thing would be to be able to opt-in to having the HasField instances be available in all contexts. The (not yet implemented, but accepted) "Modifiers" GHC proposal might be nice for that.

The local modules proposal imo is excellent as-is.

Why would you drop TypeFamilies? It seems fairly popular, given that it was just one vote short of getting added to GHC2021. Do you consider it a less-ideal compromise, that is subsumed by your second proposal (Core with GRTT)?

as syntax is contentious a topic as ever, David (the main proposal author) and I would like to invite you to give your input on https://github.com/ghc-proposals/ghc-proposals/pull/585, where we propose to change the syntax of the accepted proposal #522 introducing Or patterns. In particular, we'd like to know

This looks great, congratulations on completing it! I assume you didn’t get an opportunity to evaluate the delimited continuations based eff library? It would’ve been nice to see Cont included as one of the effects covered, though perhaps not available in all the systems you looked at? Maybe some future work.

I do hope qualified exports are available someday: https://github.com/ghc-proposals/ghc-proposals/pull/283

Right. Being able to disable "custom type warnings" at use sites was part of an earlier proposal (https://github.com/ghc-proposals/ghc-proposals/pull/454) but it ended up being shelved.