optional definition

[Li-yao Xia]

Link to the definition being discussed: 
https://hackage.haskell.org/package/base-4.12.0.0/docs/Control-Applicative.html#v:optional

On 9/1/19 5:27 AM, Dannyu NDos wrote:
> The current 'one or none' definition breaks the order of elements.
> 


But `optional` does try, in order, to produce one element before falling 
back to `Nothing`.

optional v = (Just <$> v) <|> pure Nothing
--           one          or       none


> It is more Ord-friendly to define it as 'none or one'.


Why is it a good thing for "Alternative" to be "Ord-friendly"? 
"Alternative" has little to do with "Ord" in the first place.

Cheers,
Li-yao