A very simple Haskell script that invokes ghc-pkg to uninstall cabal
packages.
Invoke
cabal-uninstall {pkg-id} [--force]
to unregister a package nameed {pkg-id} and delete the corresponding
package folder. If there are several packages with the name {pkg-id}
the script asks the user to select one. If cabal-uninstall is called
with the parameter --force, then this parameter is passed to
ghc-pkg unregister to unregister a package even if it breaks other
packages. You might have to provide root privileges to
cabal-uninstall to delete the folder.