Haskell environment hosed post reinstall

Question

I\'ve recently reinstalled my Haskell environment as I thought I had hosed it beyond recovery after updating my Mac OS X to Mavericks.

Now every time I run cabal i

Answer 1

the problem stems from the fact that cabal can track multiple versions of the same package.

Running:

cabal install --reinstall Cabal-1.18.1.3

fixes the problem