Comparing StableNames of different type

Simon Marlow marlowsd at
Fri Aug 24 11:08:03 CEST 2012

On 24/08/2012 07:39, Emil Axelsson wrote:
> Hi!
> Are there any dangers in comparing two StableNames of different type?
>    stEq :: StableName a -> StableName b -> Bool
>    stEq a b = a == (unsafeCoerce b)
> I could guard the coercion by first comparing the type representations,
> but that would give me a `Typeable` constraint that would spread
> throughout the code.

I think that's probably OK.  It should be safe even if the types are 
different, but I presume you expect the types to be the same, since 
otherwise the comparison would be guaranteed to return False, right?


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