incorrect dependencies on template-haskell

Brandon Moore brandon_m_moore at
Mon Oct 3 20:47:44 CEST 2011

> From: Antoine Latter <aslatter at>

> Sent: Sunday, October 2, 2011 9:21 PM
> On Sun, Oct 2, 2011 at 8:31 PM, Brandon Moore <brandon_m_moore at> 
> wrote:
>>  If the package isn't meant to be upgraded, should it be on
>>  hackage at all?
> Using an install of the template-haskell library other than the one
> GHC was built against will make GHC unhappy - the operations in the
> library won't type-check against the built-in GHC magic.

If so, the package should not be on hackage with dependencies that lead
cabal-install to try to upgrade it. I see three ways to fix this

  1) Remove template-haskell from the package index (perhaps keeping
      the documentation somehow)
  2) Strengthen the dependencies enough to force the GHC version
  3) Fix cabal-install to avoid the package.

I don't understand the situation well enough yet, but #1 sounds good
if the package is just on hackage for documentation links, and the set of
libraries tied to a specific compiler is the same for past ghc versions and
other compillers.


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