Questions regarding Bounded

[David Feuer]

Best solution, IMO: don't give Down a Num instance.

On Sat, May 9, 2020, 5:55 PM David Feuer <david.feuer at gmail.com> wrote:

> The question of the Enum instance is left a bit unsatisfactory. It can
> either match the Num instance or the Bounded instance but not both. Ugh!
>
> On Sat, May 9, 2020, 5:51 PM Carter Schonwald <carter.schonwald at gmail.com>
> wrote:
>
>> Agreed.  The min of a total order should be the min.  This seems to be a
>> straight up bug.
>>
>> On Sat, May 9, 2020 at 5:34 PM David Feuer <david.feuer at gmail.com> wrote:
>>
>>> I'd call that a bug in the Down instance myself, and a serious one!
>>>
>>> On Sat, May 9, 2020, 5:30 PM Joseph C. Sible <josephcsible at gmail.com>
>>> wrote:
>>>
>>>> On Mon, May 4, 2020 at 7:55 AM Simon Jakobi via Libraries
>>>> <libraries at haskell.org> wrote:
>>>> >
>>>> > Are there any instances where
>>>> >
>>>> > minBound <= x == True
>>>> >
>>>> > and
>>>> >
>>>> > maxBound >= x == True
>>>> >
>>>> > don't hold for every x?
>>>>
>>>> Yes:
>>>>
>>>> minBound <= Data.Ord.Down (1 :: Int) == False
>>>>
>>>> IMO, this is kind of a wart in Down, as I commented at
>>>> https://gitlab.haskell.org/ghc/ghc/-/merge_requests/881#note_271111
>>>>
>>>> Joseph C. Sible
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