[Haskell-cafe] mtl and transformers

Valery V. Vorotyntsev valery.vv at gmail.com
Mon Jan 11 02:54:13 EST 2010

>> Günther Schmidt:
>>> Could not find module `Control.Monad.Trans':
>>>  it was found in multiple packages: transformers-
>>>  mtl-

> Ivan Lazar Miljenovic:
>> There's a way of specifying it at the top of whichever file you're
>> using, but so far my workaround in this situation is to use "ghc-pkg
>> hide" on whichever of those packages I don't use in my code.

Günther Schmidt:
> ghc-pkg hide works fine, thanks!

As an alternative, you can use `LANGUAGE PackageImports' pragma:

| {-# LANGUAGE PackageImports #-}
| import "transformers" Control.Monad.Trans


PS: Have fun with iteratees!


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