8.2.1: Ord TyCon is gone?

29 Jul 2017

      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..

Thanks,

-Levent.

8.2.1: Ord TyCon is gone?

Levent Erkok