[Haskell-cafe] Introducing Instances in GHC point releases

[Henning Thielemann]

John Goerzen schrieb:
> So this is annoying (CCing -cafe)
> 
> I need NominalDiffTime and UTCTime to have Typeable instances.  In
> 6.10.1, they didn't ship with them out of the box, so I added them.
> Apparently, in 6.10.3, they DO ship with those instances out of the box.
> 
> Annoyingly, that means that my code breaks on 6.10.3.

After having conflicting instances several times with some types in the
past, I came to the conclusion that I should never define orphan
instances. Can you restrict your package to 6.10.3 where an "official"
instance is available?

http://www.haskell.org/haskellwiki/Orphan_instance