[commit: packages/template-haskell] master: Make Pred a type synonym of Type (issue #7021) (57b662c)

Mateusz Kowalczyk fuuzetsu at fuuzetsu.co.uk
Sun Mar 23 01:05:28 UTC 2014

On 23/03/14 00:45, Richard Eisenberg wrote:
> Note that the removal of `classP` is only for HEAD -- it will *not* be merged in for 7.8, which would be way too big a change at this point.
> Richard
> On Mar 22, 2014, at 4:53 PM, Mateusz Kowalczyk wrote:
>> On 22/03/14 20:37, Johan Tibell wrote:
>>> What's the right way to fix libraries (e.g. aeson) that break because
>>> classP was removed?
>> I have already patched lens, aeson, free, derive and binarydefer. You
>> can look for commits with my e-mail in those projects for how it was done.
>> All you need to do now to get aeson to compile on 7.9 is to get Bryan to
>> upload a new version with the relevant commit on Hackage.
>> -- 
>> Mateusz K.
>> _______________________________________________
>> ghc-devs mailing list
>> ghc-devs at haskell.org
>> http://www.haskell.org/mailman/listinfo/ghc-devs

Right. I've been using __GLASGOW_HASKELL__ CPP tokens to bound this off
so far. Is there a reason why the Template Haskell version wasn't bumped
after this change? This makes it impossible to instead use tokens that
work based on TH version rather than GHC version. As far as I can tell,
what's shipping with 7.8 is TH and the breaking change that's
currently in 7.9 is also TH

Mateusz K.

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