8.2.1: Ord TyCon is gone?

[Niklas Hambüchen]

Hi Levent,

that seems to be this commit, part of the making-ghc-deterministic effort:

  https://ghc.haskell.org/trac/ghc/ticket/4012#comment:213

CC @niteria who might be answer your question.

Niklas

On 29/07/17 08:12, Levent Erkok wrote:
> I'm trying to port some plugin code from GHC 8.0.2 to GHC 8.2.1; alas
> I'm getting an error suggesting that TyCon is no longer an instance of
Ord:
>
> Data/SBV/Plugin/Analyze.hs:580:33: error:
>     • No instance for (Ord TyCon) arising from a use of ‘M.lookup’
>       There are instances for similar types:
>         instance Ord GHC.Types.TyCon -- Defined in ‘GHC.Classes’
>     • In the expression: k `M.lookup` tcMap
>       In the expression:
>         case k `M.lookup` tcMap of
>           Just knd -> return knd
>           Nothing -> unknown
>       In a case alternative:
>           Just k
>             -> case k `M.lookup` tcMap of
>                  Just knd -> return knd
>                  Nothing -> unknown
>     |
> 580 |                  Just k -> case k `M.lookup` tcMap of
>     |                                 ^^^^^^^^^^^^^^^^^^
>
> I was using TyCon's as a key in a map, but that code is no longer
> compiling. I've looked through the release notes but couldn't find what
> the new mechanism is.
>
> I'd appreciate if someone can point me in the right direction regarding
> how to use TyCon as a map key..