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A comment on State Monad for the Rest of Us. Parent comment

Re:State Monad for the Rest of Us by greener_grass on Friday August 09, 2024 @11:40AM (#41202908)
Is there are correct way around?

    St -> (a, St)
vs

    St -> (St, a)
I've found both in the wild and it can be very confusing!
[ Parent | on HN ]
Re:State Monad for the Rest of Us by chuckadams on Friday August 09, 2024 @11:47AM (#41202957)
The order doesn’t matter as long as you’re consistent, but Control.Monad.State uses the first, and you’ll have a bad time (in Haskell anyway) if you’re not compatible with that.
[ Parent | on HN ]
Re:State Monad for the Rest of Us by RandomThoughts3 on Friday August 09, 2024 @12:51PM (#41203483)
It’s the same thing. Order doesn’t matter in the tuple. Just use a bind which is in line with the signature of the type you want to use.
[ Parent | on HN ]