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I think there are monads that are reasonably intuitive - Promises, Option types, etc (I know promises are ~technically~ not monads). It's mainly the practice of incorporating state into a stateless language and all the weirdness that entails that's the problem, in my view (so, specifically the IO monad)

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> (I know promises are ~technically~ not monads)

Do you mean promises in general, or the concrete implementation in js? I've got it in my head that promises the pattern are monadic, but js stuffs it (e.g. by up by making .then() automatically flatten if the callback also returns a promise)

That sounds right. I'm not exactly sure

Yeah that's correct. The built-in implementation of Promise violates some of the interfaces monads need to follow, including that auto flatten. But it's definitely possible to have a monadic promise (or future or whatever).

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