Minor containers API changes

[Felipe Almeida Lessa]

On Sun, Dec 4, 2011 at 3:37 PM, Edward Z. Yang <ezyang at mit.edu> wrote:
> Excerpts from Felipe Almeida Lessa's message of Sun Dec 04 08:06:36 -0500 2011:
>> Which ones?  The Ord instance of 'Reverse (Reverse k)'s should be the
>> same as that of 'k', right?  Other than that, what invariants could be
>> broken?
>
> Yes, Reverse (Reverse k)) should be functionally equal to k, but that's
> not what reverse' was doing, was it? ;-)

It seems I may have missed something then.  It gets a map with keys of
type 'Reverse k', uses 'reverse' to get 'Reverse (Reverse k)' and then
unsafeCoerces to 'k'.  Doesn't it?  =)

Cheers,

-- 
Felipe.