Add instance Bounded (Ratio a)

David Feuer david.feuer at gmail.com
Sun Jun 16 18:49:14 UTC 2019


Agreed. Moreover, even if we had some magical way to avoid overflow issues,
there's no guarantee that

  maxBound % 1 >= minBound % (-1)

or that

  minBound % 1 <= maxBound % (-1)

So I think this is fundamentally doomed.

On Sun, Jun 16, 2019, 2:30 PM Eric Mertens <emertens at gmail.com> wrote:

> Ratio only only generally be used with Integer, which isn’t itself an
> instance of Bounded. This probably wouldn’t be a very useful instance. It
> has overflow issues with Bounded types like Int for various operations
> including comparisons.
>
> On Jun 16, 2019, at 10:14 AM, Vanessa McHale <vanessa.mchale at iohk.io>
> wrote:
>
> Signed PGP part
>
> Seems sensible. Out of curiosity, what would this help with?
> On 6/14/19 6:44 PM, Dannyu NDos wrote:
>
> instance (Integral a, Bounded a) => Bounded (Ratio a) where
>     minBound = minBound % 1
>     maxBound = maxBound % 1
>
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