Re: [snap] can't install snaplet-hdbc, duplicate type signature

[MightyByte]

This is caused by a problem in data-lens-template-2.1.6.  You need to upgrade to the recently released 2.1.7.  The following commands should correct the problem:

ghc-pkg unregister data-lens-template --force

ghc-pkg unregister snap --force

cabal update

cabal install snaplet-hdbc

On Tue, Sep 18, 2012 at 10:17 PM, Chris Kahn <christop...@gmail.com> wrote:

Hey all,

I'm relatively new to Haskell, been learning for the last 6 months or so and had a class in university that covered the basics. So I decided I'd give the Snap framework a spin on my machine. It's a relatively new machine so this is a fresh install of Haskell (GHC 7.4.1) on Ubuntu 12.04. I installed Snap, created a skeleton project etc, and then went and did cabal install snaplet-hdbc and it started compiling things and loading packages, and finally spat out this error:

src/Snap/Snaplet/Internal/Types.hs:82:1:

    Duplicate type signature:

      src/Snap/Snaplet/Internal/Types.hs:82:1-47: snapletConfig ::

                                                    Lens (Snaplet a) SnapletConfig

      src/Snap/Snaplet/Internal/Types.hs:76:1-39: snapletConfig ::

                                                    forall s_aySX.

                                                    Lens (Snaplet s_aySX) SnapletConfig

src/Snap/Snaplet/Internal/Types.hs:87:1:

    Duplicate type signature:

      src/Snap/Snaplet/Internal/Types.hs:87:1-34: snapletValue ::

                                                    Lens (Snaplet a) a

      src/Snap/Snaplet/Internal/Types.hs:76:1-39: snapletValue ::

                                                    forall s_aySX. Lens (Snaplet s_aySX) s_aySX

cabal: Error: some packages failed to install:

snap-0.9.1.1 failed during the building phase. The exception was:

ExitFailure 1

Is this because of something I've configured wrong, or is it a bug in Snap? Can anybody help?

Cheers!

Chris

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