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A comment on Haskell's Children. Parent comment

Re:Haskell's Children by choeger on Wednesday September 23, 2020 @09:33AM (#24566842)
It is not. do notation is just syntactic sugar. The feature that enables re-use are the type-classes and the structure of the standard library. Interestingly, you do have traits in rust, but I think there is no monad trait yet in the std lib.
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Re:Haskell's Children by steveklabnik on Wednesday September 23, 2020 @10:22AM (#24567393)
There is not a monad trait because we do not have higher kinded types, which is a requirement.

Beyond that, it's not clear that a monad trait would work, even if we did. It may, but it also may not. We'll see (or not) I guess.

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Re:Haskell's Children by bad_user on Wednesday September 23, 2020 @01:01PM (#24569220)
Why wouldn't a Monad trait work?

You mean you couldn't express it in Rust, even with HKTs? Or you mean that it wouldn't be useful?

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Re:Haskell's Children by steveklabnik on Wednesday September 23, 2020 @01:09PM (#24569331)
Both. See here for more https://twitter.com/withoutboats/status/1027702538563477505

There have been some people working on these problems, take https://varkor.github.io/blog/2018/11/10/monadic-do-notation... for example. This is why I say "not clear" and not "impossible" or something. We just don't know.

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Re:Haskell's Children by Quekid5 on Wednesday September 23, 2020 @07:07PM (#24573308)
It's basically a research-level problem given the other constraints of Rust. (Which is fine. Trade-offs and all that.)
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