haskell - What's the best workaround for not having "cabal upgrade"?

Question

I want to upgrade all packages, not just a specific one with cabal install --upgrade-dependencies.

question from:https://stackoverflow.com/questions/6905163/whats-the-best-workaround-for-not-having-cabal-upgrade

Answer 1

This bit of shell hackery works for me on OS X:

cabal list --simple-output --installed | awk '{print $1}' | uniq | xargs -I {} cabal install {} --reinstall

EDIT: Now forces a reinstall, and avoids installing a package more than once when more than one version is present. Thanks for the comments!

EDIT YEARS LATER: Now that Cabal sandboxes and Stack exist, I strongly recommend against trying to upgrade packages in place. You'll end up with far fewer headaches if you instead can just wipe out an existing sandbox and reinstall up-to-date dependencies.