[Haskell-cafe] Would it be evil to add "deriving Typeable" to newtype Q?

Leonel Fonseca leonelfl at gmail.com
Wed May 5 12:17:25 EDT 2010


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.


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