[Typeable2] Re: ANNOUNCE: GHC 7.8.1 Release Candidate 1

[Simon Peyton Jones]

| Can you not simply let ghc-7.8 interpret TypeableN as Typeable?

Not really: ghc-7.8 does still support TypeableN I think (for backward compat reasons).  So it can't take it to mean two different things.

| -----Original Message-----
| From: Glasgow-haskell-users [mailto:glasgow-haskell-users-
| bounces at haskell.org] On Behalf Of Christian Maeder
| Sent: 20 February 2014 15:51
| To: Daniil Frumin
| Cc: glasgow-haskell-users at haskell.org
| Subject: Re: [Typeable2] Re: ANNOUNCE: GHC 7.8.1 Release Candidate 1
| 
| Yes, changing Typeable2 to Typeable in:
| 
| {-# LANGUAGE StandaloneDeriving, DeriveDataTypeable #-} ...
| deriving instance Typeable Gr
| 
| goes through with ghc-7.8-rc1.
| 
| However, this change refuses to compile with ghc-7.6.3:
| 
|      Expecting two more arguments to `Gr'
|      In the stand-alone deriving instance for `Typeable Gr'
| 
| This is unfortunate, because I need to add conditional compilation to
| make my code compilable for the two most recent major versions of GHC.
| 
| Can you not simply let ghc-7.8 interpret TypeableN as Typeable?
| 
| Cheers Christian
| 
| Am 13.02.2014 15:36, schrieb Daniil Frumin:
| > I think that the preferred solution is to get rid of the custom
| > Typeable(2) instances and just derive Typeable
| >
| > On Thu, Feb 13, 2014 at 5:22 PM, Christian Maeder
| > <Christian.Maeder at dfki.de> wrote:
| >> Hi,
| >>
| >> with ghc-7.8.20140130 I get the compilation error:
| >>
| >>      Not in scope: type constructor or class 'Typeable2'
| >>      Perhaps you meant 'Typeable' (imported from Data.Typeable)
| >>
| >> What is the recommend way to adjust my code or my dependencies?
| >>
| >> Cheers Christian
| >>
| >> Am 03.02.2014 23:35, schrieb Austin Seipp:
| >>>
| >>> We are pleased to announce the first release candidate for GHC
| 7.8.1:
| >>>
| >>>       http://www.haskell.org/ghc/dist/7.8.1-rc1/
| >>>       http://www.haskell.org/ghc/docs/7.8.1-rc1/html/
| >>>
| >>> This includes the source tarball and bindists for Windows, Linux, OS
| >>> X, FreeBSD, and Solaris, on x86 and x86_64. There is a signed copy
| >>> of the SHA256 hashes available (attached) using my GPG key (keyid
| >>> 0x3B58D86F).
| >>>
| >>> We plan to make the 7.8.1 RC2 release quite soon, as we're aware of
| >>> some existing issues.
| >>>
| >>> Please test as much as possible; bugs are much cheaper if we find
| >>> them before the release!
| >>>
| >>>
| >>>
| >>>
| >>> _______________________________________________
| >>> Glasgow-haskell-users mailing list
| >>> Glasgow-haskell-users at haskell.org
| >>> http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
| >>>
| >>
| >> _______________________________________________
| >> Glasgow-haskell-users mailing list
| >> Glasgow-haskell-users at haskell.org
| >> http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
| >
| >
| >
| 
| _______________________________________________
| Glasgow-haskell-users mailing list
| Glasgow-haskell-users at haskell.org
| http://www.haskell.org/mailman/listinfo/glasgow-haskell-users