On Mon, 2008-12-22 at 09:55 +0000, Neil Mitchell wrote:

Hi

It appears cabal doesn't know ViewPatterns are a valid extension:

Sun Oct 19 15:14:08 BST 2008 Ian Lynagh * Add GHC 6.10.1's extensions to the list in Language.Haskell.Extension This patch was added after the 1.6.0.1 release (which came with ghc-6.10.1). It'll be in 1.6.0.2.

hlint$ cabal install --global Resolving dependencies... Configuring hlint-1.0.0.1... Warning: Unknown extensions: ViewPatterns Preprocessing executables for hlint-1.0.0.1... Building hlint-1.0.0.1...

Thanks

Note that it worked despite the extension being unknown. Using unregistered extensions works so long as the compiler supports them. The only thing that we prevent is uploading packages that are using unregistered extensions. Duncan