[Haskell-beginners] Equivalence of Inheritance

Antoine Latter aslatter at gmail.com
Tue Dec 14 21:18:52 CET 2010


Sorry, I really don't know enough about what you're after to attempt that.

But you'll need to change you're signatures of the form:

> function :: Person -> Foo

to something of the form:

> function :: Person p => p -> Foo

Because again, a type class can not be used as a type.

Antoine

On Tue, Dec 14, 2010 at 2:12 PM, Russ Abbott <russ.abbott at gmail.com> wrote:
> What got fouled up is all the adjustments I had to make to the other
> declarations.
> Can you complete the example so that it compiles using
>
> class Person p where ...
>
> I'd very much like to see an example that actually compiles.
>
> Thanks.
> -- Russ
>
> On Tue, Dec 14, 2010 at 11:58 AM, Antoine Latter <aslatter at gmail.com> wrote:
>>
>> On Tue, Dec 14, 2010 at 1:52 PM, Russ Abbott <russ.abbott at gmail.com>
>> wrote:
>> > If gender is a field in a Person type, then a Person must have both an
>> > ovaryCondition and a prostateCondition.  That seems awkward.
>> > Regarding
>> >      class Person p where
>> > I started down that path but got completely fouled up.
>>
>> How did this get fouled up? Every class declaration must take
>> arguments - here, 'p' is the argument for the class.
>>
>> Thanks,
>> Antoine
>
>



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