Cabal install ghc-mod complains on broken packages (GHC 7.6.3)

Question

I use: GHC 7.6.3 on Ubuntu (installed it from current repo by apt-get install haskell-platform) .

Trying to install ghc-mod , since my ide plugin asks for it.

❯ cabal install ghc-mod             
Resolving dependencies...
In order, the following would be installed:
cmdargs-0.10.7 (new package)
convertible-1.1.0.0 (new package)
ghc-syb-utils-0.2.1.2 (new package)
hashable-1.2.1.0 (reinstall) changes: text-0.11.3.1 -> 1.1.0.1
hscolour-1.20.3 (new package)
polyparse-1.9 (new package)
cpphs-1.18.4 (new package)
haskell-src-exts-1.15.0.1 (new package)
transformers-base-0.4.2 (new package)
monad-control-0.3.3.0 (new package)
lifted-base-0.2.2.2 (new package)
io-choice-0.0.5 (new package)
unordered-containers-0.2.4.0 (reinstall)
uniplate-1.6.12 (new package)
hlint-1.8.61 (new package)
ghc-mod-4.1.0 (new package)
cabal: The following packages are likely to be broken by the reinstalls:
unordered-containers-0.2.3.0
case-insensitive-1.2.0.0
case-insensitive-1.1.0.2
Use --force-reinstalls if you want to install anyway.

What are the usual steps to resolve such a problem? (that's my first try to work with Haskell)

Answer 1

• Option 1: Stick to the haskell platform versions . See the changes lines and Try adding a constraint to use your platform text library version.

  cabal install ghc-mod --constraint=text==0.11.3.1

• Option 2: build it in a sandbox within a specific folder. You'll have to add the sandbox bin folder to the path or copy or link the executables to your $HOME/bin folder.

You will have to update cabal-install to use cabal's new sandbox feature (v.1.18+). Alternatives are cabal-dev, hsenv and virthualenv

• Option 3: Reset your libraries folders in $HOME/.ghc and $HOME/.cabal/lib