There's a flag to turn it off, does that work? Try cabal install transformers-base -f-OrphanInstances Sjoerd On May 9, 2013, at 2:47 PM, jean-christophe mincke wrote:

Hello Café

I am running into problems when installing transformers-base-0.4.1.

Has anyone an idea about what is going on?

REM : this is a "brand new" debian install, I have just install ghc, cabal install cabal-install etc.

Thank you

very much

J-C

cabal install transformers-base Resolving dependencies... Downloading transformers-base-0.4.1... Configuring transformers-base-0.4.1... Preprocessing library transformers-base-0.4.1... Building transformers-base-0.4.1... [1 of 1] Compiling Control.Monad.Base ( src/Control/Monad/Base.hs, dist/build/Control/Monad/Base.o )

src/Control/Monad/Base.hs:63:10: Duplicate instance declarations: instance Applicative (L.ST s) -- Defined at src/Control/Monad/Base.hs:63:10 instance Applicative (L.ST s) -- Defined in `Control.Applicative'

src/Control/Monad/Base.hs:67:10: Duplicate instance declarations: instance Applicative (S.ST s) -- Defined at src/Control/Monad/Base.hs:67:10 instance Applicative (S.ST s) -- Defined in `Control.Applicative' cabal: Error: some packages failed to install: transformers-base-0.4.1 failed during the building phase. The exception was: ExitFailure 1 _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe