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