[Haskell-cafe] Usage question with TemplateHaskell and Generic
magicloud.magiclouds at gmail.com
Fri Nov 11 16:08:02 CET 2011
2011/11/7 José Pedro Magalhães <jpm at cs.uu.nl>:
> I'm not sure I understand your question. But if you mean that you want to
> retrieve the type variable names, as they were defined in the source, then I
> can tell you that the generic deriving mechanism cannot do this.
> On Sun, Nov 6, 2011 at 14:35, Magicloud Magiclouds
> <magicloud.magiclouds at gmail.com> wrote:
>> I'd like to simpler the work of deriving MyClass. And I have two
>> ways to do: TemplateHaskell "$(derivingMyClass)", or Generic "deriving
>> Since I need to get the type name in the deriving, then I met this
>> question: If I have "data A b = C b", then with TemplateHaskell, the
>> type would be "VarT b", which means at compile time, I cannot get the
>> exact type, so the type name would be "b".
>> So I wonder if this could be resolved by TemplateHaskell, or Generic
>> is the only choice.
>> PS: I have not tried to do this in Generic.
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>> Haskell-Cafe at haskell.org
Thank you. After deeply thinking about this, GH sure does not....
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