Hi!

I wanted to check out great new OverloadedLists [0] feature, but got an error as in [1].

What am I doing wrong?

Thanks.

[0]: https://www.haskell.org/ghc/docs/7.8.1/html/users_guide/type-class-extensions.html#overloaded-lists
[1]: https://gist.github.com/k-bx/10574806