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Comment by dnnddidiej | Hacker News Reader

Can we have Exception monads? Asking for friend.

> Can we have Exception monads? Asking for friend.

This is nonsensical. Monads define a strict set of behaviors formalized as "monad laws"[0].

Perhaps what you want is a container which adheres to monad laws capable of abstracting exceptions. Two exemplars of same are Haskell's Data.Either[1] and Scala's Either[2].

0 - https://wiki.haskell.org/Monad_laws

1 - https://hackage-content.haskell.org/package/base-4.22.0.0/do...

2 - https://www.scala-lang.org/api/3.8.3/scala/util/Either.html

I don't think it's nonsensical, it's just another name for the same thing. E.g. in the Haskell wiki it says, "the Error monad, also called the Exception monad".

https://wiki.haskell.org/index.php?title=All_About_Monads

I was unaware of "Exception monad" being an industry equivalent term for Either/Error. Given no other context, desiring an "Exception monad" could be interpreted as "a type which handles raising Exception types." Which is how I did.

Thank you for clarifying this for me.

> Perhaps what you want is a container which adheres to monad laws capable of abstracting exceptions

That is what I meant. Struggling to picture what the other "nonsensical" thing is.

As I commented here[0], my interpretation of:

  Can we have Exception monads? Asking for friend.

Was a desire to have "a type which handles raising Exception types." Until now, I was unaware of "Exception monad" being an alternate moniker for Either/Error types.

0 - https://news.ycombinator.com/item?id=48318468

Reply on news.ycombinator.com