Roman Cheplyaka | 27 Jan 21:17 2013

GHC.Generics and newtypes

Hi,

Is it possible to generate different instances for newtypes and
datatypes using GHC.Generics?

Roman
José Pedro Magalhães | 27 Jan 21:29 2013
Picon

Re: GHC.Generics and newtypes

Hi Roman,

Yes, the automatic derivation of Generic instances does not see through newtypes.


Cheers,
Pedro

On Sun, Jan 27, 2013 at 8:17 PM, Roman Cheplyaka <roma <at> ro-che.info> wrote:
Hi,

Is it possible to generate different instances for newtypes and
datatypes using GHC.Generics?

Roman

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_______________________________________________
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Roman Cheplyaka | 27 Jan 21:34 2013

Re: GHC.Generics and newtypes

Sorry, I wasn't clear. What I want is somehow to find out whether the
type under consideration is declared using data or newtype.

Is it possible?

Roman

* José Pedro Magalhães <jpm <at> cs.uu.nl> [2013-01-27 20:29:52+0000]
> Hi Roman,
> 
> Yes, the automatic derivation of Generic instances does not see through
> newtypes.
> 
> 
> Cheers,
> Pedro
> 
> On Sun, Jan 27, 2013 at 8:17 PM, Roman Cheplyaka <roma <at> ro-che.info> wrote:
> 
> > Hi,
> >
> > Is it possible to generate different instances for newtypes and
> > datatypes using GHC.Generics?
> >
> > Roman
> >
> > _______________________________________________
> > Haskell-Cafe mailing list
> > Haskell-Cafe <at> haskell.org
> > http://www.haskell.org/mailman/listinfo/haskell-cafe
> >
José Pedro Magalhães | 27 Jan 21:36 2013
Picon

Re: GHC.Generics and newtypes

Ah, no. But that would be easy to add to the Datatype class, I think. Perhaps
open a feature request?


Cheers,
Pedro

On Sun, Jan 27, 2013 at 8:34 PM, Roman Cheplyaka <roma <at> ro-che.info> wrote:
Sorry, I wasn't clear. What I want is somehow to find out whether the
type under consideration is declared using data or newtype.

Is it possible?

Roman

* José Pedro Magalhães <jpm <at> cs.uu.nl> [2013-01-27 20:29:52+0000]
> Hi Roman,
>
> Yes, the automatic derivation of Generic instances does not see through
> newtypes.
>
>
> Cheers,
> Pedro
>
> On Sun, Jan 27, 2013 at 8:17 PM, Roman Cheplyaka <roma <at> ro-che.info> wrote:
>
> > Hi,
> >
> > Is it possible to generate different instances for newtypes and
> > datatypes using GHC.Generics?
> >
> > Roman
> >
> > _______________________________________________
> > Haskell-Cafe mailing list
> > Haskell-Cafe <at> haskell.org
> > http://www.haskell.org/mailman/listinfo/haskell-cafe
> >

_______________________________________________
Haskell-Cafe mailing list
Haskell-Cafe <at> haskell.org
http://www.haskell.org/mailman/listinfo/haskell-cafe
Roman Cheplyaka | 27 Jan 21:39 2013

Re: GHC.Generics and newtypes

Sure. Should it go to the GHC bug tracker?

Roman

* José Pedro Magalhães <jpm <at> cs.uu.nl> [2013-01-27 20:36:54+0000]
> Ah, no. But that would be easy to add to the Datatype
> class<http://hackage.haskell.org/packages/archive/base/4.6.0.0/doc/html/GHC-Generics.html#g:3>,
> I think. Perhaps
> open a feature request?
> 
> 
> Cheers,
> Pedro
> 
> On Sun, Jan 27, 2013 at 8:34 PM, Roman Cheplyaka <roma <at> ro-che.info> wrote:
> 
> > Sorry, I wasn't clear. What I want is somehow to find out whether the
> > type under consideration is declared using data or newtype.
> >
> > Is it possible?
> >
> > Roman
> >
> > * José Pedro Magalhães <jpm <at> cs.uu.nl> [2013-01-27 20:29:52+0000]
> > > Hi Roman,
> > >
> > > Yes, the automatic derivation of Generic instances does not see through
> > > newtypes.
> > >
> > >
> > > Cheers,
> > > Pedro
> > >
> > > On Sun, Jan 27, 2013 at 8:17 PM, Roman Cheplyaka <roma <at> ro-che.info>
> > wrote:
> > >
> > > > Hi,
> > > >
> > > > Is it possible to generate different instances for newtypes and
> > > > datatypes using GHC.Generics?
> > > >
> > > > Roman
> > > >
> > > > _______________________________________________
> > > > Haskell-Cafe mailing list
> > > > Haskell-Cafe <at> haskell.org
> > > > http://www.haskell.org/mailman/listinfo/haskell-cafe
> > > >
> >

Gmane