Proposal: add Bounded instances for Maybe and Either

Ivan Lazar Miljenovic ivan.miljenovic at
Wed May 9 04:30:02 UTC 2018

On 9 May 2018 at 12:15, Edward Kmett <ekmett at> wrote:
> minBound = Left minBound <= Left a < Right b <= Right maxBound = maxBound
> fits with the behavior of the existing Ord instance.
> On the other hand, Left (), being strictly less than minBound would rather
> drastically undermine the expected interaction of Ord and Bounded.

Fair enough.  I had also missed in David's initial proposal that we
had Bounded on both a and b in (Either a b).

I'm +1 on these instances (more from a "they're the logical instances"
PoV than "this will be useful").

Ivan Lazar Miljenovic
Ivan.Miljenovic at

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