I am the Chief Custodial Technician at Rent Application, a former options trader & passionate QBASIC developer. I like country music, bourbon, Words With Friends, ice cream, Crossfit, Louis CK, and Zooey Deschanel.

Unsupported extension: LambdaCase (Haskell, Cabal)

If you landed here, you are probably new to Haskell and somehow ran into this error message while installing something using cabal:

"Unsupported extension: LambdaCase"

You’re probably using a version of Haskell that’s too old canadian free slots (like whatever came on your default *nix installation).

LambdaCase was added in 7.6.1. It is a purely syntactic extension.

You should use Haskell Platform instead of whatever ghc you’ve got on your machine now.

If you’re running Ubuntu 12.04 (Precise) or earlier (“cat /etc/lsb-release” to find out what version you are running), your package manager ships with a Haskell Platform that includes a GHC that is too old.  If that’s the case, you can install GHC directly.

Thanks to Iceland_jack, jle`, and kqr in #haskell for pointing me in the right direction when I ran into this.