On Nov 17, 2009, at 8:42 AM, Valery V. Vorotyntsev wrote:

[*] I just tried to add `-hide-package mtl' to OPTIONS_GHC pragma,
with no success, and was googling for a clue.

I don't think that works, but you can do:

{-# LANGUAGE PackageImports #-}

import "transformers" Control.Monad.Reader

in GHC 6.10 and higher. I think you could even do:

{-# LANGUAGE PackageImports #-}

import "transformers" Control.Monad.Reader

import "mtl" Control.Monad.Writer

- jeremy