[Haskell-cafe] Control.Exceptions and MonadIO

oleg at pobox.com oleg at pobox.com
Sat Apr 22 00:40:32 EDT 2006

Robert Dockins wrote:
> One additional (very unfortunate) point is that higher-order IO monad
> combinators will not work on your monad, eg, the ones in
> Control.Exception.

Although that is true in general, for many useful and interesting
cases (including ReaderT, the state transformer, and the newtype wrapping
of IO) one _can_ use catch, bracket etc. constructs in MonadIO. Please
see this message and the follow-up discussion:


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