I'd recommend checking out Control.Exception.Lifted from lifted-base: http://haddocks.fpcomplete.com/fp/7.4.2/20130922-179/lifted-base/Control-Exc... On Thu, Oct 10, 2013 at 11:53 AM, Olivier Iffrig wrote:

Hello,

I'm trying to build an application with a monad encapsulating its state, environment, ... For the sake of simplicity, let's say

data MyState type Main = StateT MyState IO

But I would like to use something like bracket with my Main monad, and I did not find how to to it.

I'm looking for something like bracket' :: MonadIO m => m a -> (a -> m b) -> (a -> m c) -> m c

or in my case myBracket :: Main a -> (a -> Main b) -> (a -> Main c) -> Main c

Searching for that on hoogle did not give me anything interesting... Did someone encounter this problem, and have a solution ?

-- Olivier

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