diff --git a/Control/Monad/Interleave.hs b/Control/Monad/Interleave.hs
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+++ b/Control/Monad/Interleave.hs
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+-----------------------------------------------------------------------------
+-- |
+-- Module     : Control.Monad.Interleave
+-- Copyright  : Copyright (c) , Patrick Perry <patperry@stanford.edu>
+-- License    : BSD3
+-- Maintainer : Patrick Perry <patperry@stanford.edu>
+-- Stability  : experimental
+--
+-- Monads with an unsaveInterleaveIO-like operation.
+--
+
+module Control.Monad.Interleave (
+    MonadInterleave(..),
+    ) where
+
+import Control.Monad.ST
+import qualified Control.Monad.ST.Lazy as Lazy
+import System.IO.Unsafe
+
+-- | Monads that have an operation like 'unsafeInterleaveIO'.
+class Monad m => MonadInterleave m where
+    -- | Get the baton from the monad without doing any computation.
+    unsafeInterleave :: m a -> m a
+
+instance MonadInterleave IO where
+    unsafeInterleave = unsafeInterleaveIO
+    {-# INLINE unsafeInterleave #-}
+    
+instance MonadInterleave (ST s) where
+    unsafeInterleave = unsafeInterleaveST
+    {-# INLINE unsafeInterleave #-}
+    
+instance MonadInterleave (Lazy.ST s) where
+    unsafeInterleave = Lazy.unsafeInterleaveST
+    {-# INLINE unsafeInterleave #-}
diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
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+Copyright (c) Patrick Perry <patperry@stanford.edu> 2009
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+
+1. Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
+
+3. Neither the name of the author nor the names of his contributors
+   may be used to endorse or promote products derived from this software
+   without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGE.
diff --git a/Setup.lhs b/Setup.lhs
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+++ b/Setup.lhs
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+#!/usr/bin/env runhaskell
+> import Distribution.Simple
+> import System.Cmd
+>
+> main = defaultMain
+>
diff --git a/monad-interleave.cabal b/monad-interleave.cabal
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--- /dev/null
+++ b/monad-interleave.cabal
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+name:            monad-interleave
+version:         0.1
+homepage:        http://github.com/patperry/monad-interleave
+synopsis:        Monads with an unsaveInterleaveIO-like operation.
+description:
+    A type class for monads that have an \"unsafeInterleave\" operation.
+    Instances are provided for IO and both strict and lazy ST.
+category:        Monads
+license:         BSD3
+license-file:    LICENSE
+copyright:       (c) 2009. Patrick Perry <patperry@stanford.edu>
+author:          Patrick Perry
+maintainer:      Patrick Perry <patperry@stanford.edu>
+cabal-version: >= 1.2.0
+build-type:      Custom
+tested-with:     GHC ==6.10.1
+
+library
+    exposed-modules: Control.Monad.Interleave
+    build-depends:   base
+    ghc-options:     -Wall