Comparing StableNames of different type
nicolas.frisby at gmail.com
Tue Aug 28 18:08:24 CEST 2012
On Tue, Aug 28, 2012 at 3:34 AM, Simon Marlow <marlowsd at gmail.com> wrote:
>>>> On 24/08/2012 07:39, Emil Axelsson wrote:
>>>>> Are there any dangers in comparing two StableNames of different type?
>>>>> stEq :: StableName a -> StableName b -> Bool
>>>>> stEq a b = a == (unsafeCoerce b)
> Ok, I've added it. It will be in GHC 7.8.1.
Might we benefit from having a variant that returns Maybe (a :=: b)?
Is that safe? I have limited experience with StableNames, but that
intuitively seems safe. But polymorphism and references deserve more
thought than I've given this yet.
I'm referring to "data (:=:) :: * -> * -> * where Refl :: (a :=: a)",
just to be clear.
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