[Haskell-cafe] Exposing a GADT-provided dictionary

[Kosyrev Serge]

On 10/16/2017 02:56 PM, Li-yao Xia wrote:
>
> Would refactoring the type like this work for you?
> 
>> data GADT a where
>>   G :: HasDict a => Tag -> a -> GADT a
>>
>> data Tag = Tag1 | ... | Tagn
>>
>> withGADTDict :: ...
>> withGADTDict body x = x & case x of
>>   G _ _ -> body
Li, thank you for your reply!

I've needed the GADT clauses for their different structure,
so I've had to add a layer of structural indirection to a plain ADT.

But the spirit of your suggestion (to reduce the dict-providing GADT to
a single clause) was all the same.

-- 
с уважениeм / respectfully,
Kosyrev Serge

PGP Key ID: 3F62F118E38BED6D
--
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