[Haskell-cafe] ghc error: requested module name differs from name found in interface file

[Larry Evans]

With a file containing:

 > module Main where
 >
 > import Array
 > import Control.Functor.Fix
I get:

 > make
 > ghc -i/root/.cabal/lib/category-extras-0.53.5/ghc-6.8.2 -c 
catamorphism.example.hs
 >
 > catamorphism.example.hs:19:0:
 >     Bad interface file: 
/root/.cabal/lib/category-extras-0.53.5/ghc-6.8.2/Control/Functor/Fix.hi
 >         Something is amiss; requested module 
main:Control.Functor.Fix differs from name found in the interface file 
category-extras-0.53.5:Control.Functor.Fix
 > make: *** [all] Error 1
I used cabal to install category-extras:

 > /home/evansl/download/haskell/libs # cabal install category-extras
 > Resolving dependencies...
 > Downloading category-extras-0.53.5...
 > Configuring category-extras-0.53.5...
 > Preprocessing library category-extras-0.53.5...
...
 > /usr/bin/ar: creating dist/build/libHScategory-extras-0.53.5.a
 > Installing library in /root/.cabal/lib/category-extras-0.53.5/ghc-6.8.2
 > Registering category-extras-0.53.5...
 > Reading package info from "dist/installed-pkg-config" ... done.
 > Saving old package config file... done.
 > Writing new package config file... done.
 > /home/evansl/download/haskell/libs #
What should I do to import the Functor.Fix as shown here:

http://comonad.com/reader/2008/recursion-schemes/

TIA.

-Larry