I think the origin of the suffix 1 is e.g. the function foldr1 :: (a -> a -> a) -> [a] -> a which is a fold for non-empty lists only. That use of "1" might be older than the use of "1" for order-1 type constructors. On 2019-09-20 03:56, Ruben Astudillo wrote:
On 19-09-19 22:17, Alexandre Esteves wrote:
I do like the sound of `instance Foldable1 Set1` more than I do `instance NonEmptyFoldable NonEmptySet` https://hackage.haskell.org/package/semigroupoids-5.3.3/docs/Data-Semigroup-...
I prefer it too, I just wish (future) documentation included a little explanation on why the suffix 1 was put.
-- Andreas Abel <>< Du bist der geliebte Mensch. Department of Computer Science and Engineering Chalmers and Gothenburg University, Sweden andreas.abel@gu.se http://www.cse.chalmers.se/~abela/