[Haskell-cafe] Inheritance and Wrappers
ozgurakgun at gmail.com
Thu Feb 3 11:19:37 CET 2011
On 3 February 2011 02:35, Brandon Moore <brandon_m_moore at yahoo.com> wrote:
> Here's one thing to consider:
> Can you write a function
> f :: (Data a) => a -> String
> f x = termTag x
> It would seem the Data a => Term a instance justifies
> this function, and it will always use the default instance.
> Now, what happens if "f" is applied to a value of some type
> T which is an instance of Data, but has a custom Term instance?
Great point, thanks!
I guess somehow you shouldn't be allowed to write that function "f". I need
to think about this one.
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