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Is it evil to add deriving Typeable to newtype Q?

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Leonel Fonseca — 1273047213Wed, 05 May 2010 08:13:33 +0000 (UTC) 
Hi everybody,

Is it reasonable to add "deriving Typeable" to newtype Q?

In case you wonder why I want to do that, it is because I've constructed a Q
[Dec] inside a monad, I want to extract  it from the monad (via runIO) and
the monad has constraint "Typeable" over this parameter.

I've also tried to write the Typeable instance in my own module (not
Language.Haskell.TH.Syntax). But I've got no luck since the Q type
constructor is exported but the data constructor is not.

Thanks.
Robert Greayer — 1273072939Wed, 05 May 2010 15:22:19 +0000 (UTC) 
On Wed, May 5, 2010 at 4:13 AM, Leonel Fonseca  wrote:
> Hi everybody,
>
> Is it reasonable to add "deriving Typeable" to newtype Q?
>
> In case you wonder why I want to do that, it is because I've constructed a Q
> [Dec] inside a monad, I want to extract  it from the monad (via runIO) and
> the monad has constraint "Typeable" over this parameter.
>
> I've also tried to write the Typeable instance in my own module (not
> Language.Haskell.TH.Syntax). But I've got no luck since the Q type
> constructor is exported but the data constructor is not.
>
> Thanks.
> --
>
> Leonel Fonseca.
>
> _______________________________________________
> template-haskell mailing list
> 
> http://www.haskell.org/mailman/listinfo/templ...
>
>
This question might be better asked at Haskell-Cafe --
template-haskell (the mailing list) is pretty quiet, and TH questions
are perfectly appropriate on -Cafe.  The separate template-haskell
mailing list is perhaps edging toward retirement.
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