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diff --git a/src/Rahm/Desktop/Layout/ReinterpretMessage.hs b/src/Rahm/Desktop/Layout/ReinterpretMessage.hs
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+module Rahm.Desktop.Layout.ReinterpretMessage where
+
+import XMonad (SomeMessage, X)
+import XMonad.Layout.LayoutModifier (LayoutModifier(..))
+import Data.Proxy (Proxy (..))
+
+-- This is a type class that defines how to reinterpret a message. One can think
+-- of this as a kind of type-level function. It lets one associate a function
+-- (reinterpretMessage) with a type construct, which for the case below is a
+-- Symbol.
+--
+-- It would be nice to attach this function to the LayoutModifier directly as a
+-- value, however LayoutModifiers must be Show-able and Read-able and functions
+-- are not. However encoding in the typesystem itsef which function is to be
+-- called is the best alternative I have.
+class DoReinterpret (k :: t) where
+  reinterpretMessage ::
+    Proxy k -> SomeMessage -> X (Maybe SomeMessage)
+
+-- Data construct for association a DoReinterpret function with a concrete
+-- construct that can be used in the LayoutModifier instance.
+--
+-- It wolud be nice to have ReinterpretMessage hold the function as a value
+-- rather than delegate to this kind-instance, however, it won't work because
+-- LayoutModifiers have to be Read-able and Show-able, and functions are neither
+-- of those, so a value-level function may not be a member of a LayoutModifier,
+-- thus I have to settle for delegating to a hard-coded instance using
+-- type-classes.
+data ReinterpretMessage k a = ReinterpretMessage
+  deriving (Show, Read)
+
+-- Instance for ReinterpretMessage as a Layout modifier.
+instance (DoReinterpret k) =>
+      LayoutModifier (ReinterpretMessage k) a where 
+
+  handleMessOrMaybeModifyIt self message = do
+
+    -- Delegates to the reinterpretMessage function associatied with the
+    -- type-variable k.
+    newMessage <- reinterpretMessage (ofProxy self) message
+    case newMessage of
+      Just m -> return $ Just $ Right m
+      Nothing -> return $ Just $ Left self
+    where
+      -- ofProxy just provides reifies the phantom type k so the type system can
+      -- figure out what instance to go to.
+      ofProxy :: ReinterpretMessage k a -> Proxy k
+      ofProxy _ = Proxy