Resolving dependencies... cabal: Could not resolve dependencies: next goal: ghci-haskeline (user goal) rejecting: ghci-haskeline-0.2 (global constraint requires ==0.1.1) trying: ghci-haskeline-0.1.1 next goal: ghc (dependency of ghci-haskeline-0.1.1) rejecting: ghc-7.10.2/installed-a64... (conflict: ghc => array==0.5.1.0/installed-d42..., ghci-haskeline => array>=0.1 && <0.3) Dependency tree exhaustively searched.