[Haskell-beginners] Data declarations

Brandon Allbery allbery.b at gmail.com
Fri Jun 3 17:44:52 CEST 2011

On Fri, Jun 3, 2011 at 09:37, aditya siram <aditya.siram at gmail.com> wrote:
>> One more question, out of curiosity: In your above example, you could change
>>  data Populated = Populated
>>  data New = New
>> to simply
>>  data Populated
>>  data New
>> correct? You might as well, right, since your constructors take no
>> values, and you are just using them as phantom types?
> Yes I think that's correct. You might also look at GADT's [1] which
> cover some of the same use-cases.

The reason for the former is that the latter is not accepted by
Haskell 98, so it's a little less portable.

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