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by whateveracct 2473 days ago
My favorite part about Haskell is how you can know literally nothing about the domain and make meaningful changes to programs regardless thanks to local reasoning.

That's really one power of functor/applicative/monad - if you understand their interfaces, you can work with new unfamiliar types that have these instances without much effort at all.
2 comments
BucketSort 2473 days ago
It's amazing. No one could ever do something like this with an imperative language!
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whateveracct 2472 days ago
Nobody ever said that :)

Although abstracting over this stuff isn't possible in any imperative language unless Scala or maybe advanced C++ template count. But that isn't due to their imperative nature exactly.

But local reasoning is very hard to count on in most other languages - that's for sure. It's easier to just run a VM in your head.

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lonelappde 2472 days ago
It's literally a meaningless change! :-) All refractorings at meaningless changes, by definition and design.

Purity's power is that beautiful meaningless changes are safe.

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