Arg has unlawful instances

[chessai .]

In what way is the documentation for Eq (as of base 4.12) overzealous, and
how would you suggest it be changed?

Thanks

On Sat, May 11, 2019, 3:35 AM Edward Kmett <ekmett at gmail.com> wrote:

> -1
>
> I agree with Henning on this one.
>
> (==) provides an equivalence relation.
>
> Despite the addition of some vocabulary in base 4.12 about how (==)
> "should" be structural, that is at odds with Arg's actual purpose.
>
> I'd rather argue that the attempted refinement of (==)'s documentation was
> rather overzealous than that Arg as it is defined is wrong.
>
> The instances are useful and follow the intent of the classes, just not
> the extra paragraph that was bolted on sideways to the text describing Eq.
>
> -Edward
>
> On Sat, May 11, 2019 at 9:30 AM Henning Thielemann <
> lemming at henning-thielemann.de> wrote:
>
>>
>> On Fri, 10 May 2019, David Feuer wrote:
>>
>> > There also needs to be some documentation about the fact that the Arg
>> > constructor allows inspection that does not respect Eq.
>>
>> This follows from Arg's purpose.
>>
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