TypeLits and type families wrt. equality

Richard Eisenberg eir at cis.upenn.edu
Mon Jul 27 15:08:13 UTC 2015

On Jul 27, 2015, at 10:56 AM, Gabor Greif <ggreif at gmail.com> wrote:
>>> decideRefl :: Proxy (a :: Symbol) -> Proxy b
>>>              -> Proxy (Equal a b :~: 'False)
>>>              -> Either (Equal a b :~: 'False) (a :~: b)

What's the point of the third Proxy argument? I don't think it adds anything. Perhaps without that the way forward (albeit still with unsafeCoerce) will become clear.


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