drama
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evanrelf
Instances for `exceptions` classes
Since the Actor monad is basically a ReaderT, do you think it'd be possible to add instances for exception's MonadThrow, MonadCatch and MonadMask? Of course, exception handling ought to be handled a bit different in an actor-style architecture, but being able to use bracket (and similar) to manage resources is quite important nonetheless.
As an example, currently I don't believe it's possible to write an actor which uses network-simple's listen and accept, to then cast any new client socket to some manager actor.
My bad, using liftIO and withRunInIO, it is possible to use catch and whatnot, and hence achieve what I was after, but it feels a bit complicated v.s. having MonadCatch etc. available.
I prefer to keep a minimal dependency footprint. The unliftio package handles most of the standard-library-ish combinators like bracket, catch, async, etc. And for libraries like network-simple, it's possible to define orphan Monad{Throw,Catch,Mask} instances for Actor via the underlying ReaderT.
Also, drama is mostly a toy/experimental library right now; there's lots of stuff which is missing or incorrect. I wouldn't use it for anything serious.
That said, I'll consider depending on exceptions in the future.
Well, unliftio uses/depends on safe-exceptions, which pulls in exceptions anyway (it uses the very same Monad{Throw,Catch,Mask} classes), so there wouldn't really be an extra dependency, only an extra direct dependency :wink:
Sure, and orphan instance can be created (that's what I do right now), but I prefer to avoid those whenever possible.
drama depends on unliftio-core (contains just the MonadUnliftIO type class), not unliftio (contains lots of standard library stuff).