Re: Data instance for Data.Version

If the instances are hand-rolled in base, you'll need: instance Data Version where gfoldl k z (Version bs ts) = z Version `k` bs `k` ts gunfold k z c = case constrIndex c of 1 -> k (k (z Version)) _ -> error "Data.Data.gunfold(Version)" toConstr (Version _ _) = versionConstr dataTypeOf _ = versionType versionConstr :: ConstrversionConstr = mkConstr versionType "Version" ["versionBranch","versionTags"] Prefix versionType :: DataTypeversionType = mkDataType "Data.Version.Version" [versionConstr] On Thu, Sep 12, 2013 at 7:24 AM, Herbert Valerio Riedel wrote:

Hello *,

As we're still in time to get this in before the GHC 7.8 freeze and this seems to be "the right thing" to do, are there any objections to implement this (specifically, adding a `deriving Data` to `base`s Data.Version for GHC 7.8.1)?

Cheers, hvr

On 2013-03-15 at 23:29:21 +0100, Edward A Kmett wrote:

...

+1 from me. I've had to use an orphan

Sent from my iPhone

On Mar 15, 2013, at 5:56 PM, David Lazar wrote:

...

Hi,

Can we derive Data for Data.Version.Version? It would benefit Cabal.

Thanks, David

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