[Haskell-cafe] library conflicts and how to resolve them

[Graham Berks]

Attempting  

$ cabal install persistent
Resolving dependencies...
In order, the following would be installed:
aeson-0.6.0.2 (reinstall) changes: mtl-2.1.1 -> 2.0.1.0
persistent-0.9.0.3 (new package)
cabal: The following packages are likely to be broken by the reinstalls:
buildwrapper-0.5.2
Use --force-reinstalls if you want to install anyway.


Any ideas what is going on ? I believe aeson-0.6.0.2  is already installed.
And as far as I can tell the build of aeson-0.6.0.2 doesn't require that specific version of mtl.

Am I missing something ? Is there a way to force ghc to ignore this ??

Thanks 

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