Open
Description
Proposing we add these mapN
functions, and make them available to more than just List
.
map2 :: forall a b c f. Functor f => (a -> b -> c) -> f a -> f b -> f c
map3 :: forall a b c d f. Functor f => (a -> b -> c -> d) -> f a -> f b -> f c -> f d
...
map10 ...
We can then use the mapN
functions to create zipN
functions:
-- This already exists, but it would be nice to offer a more generic version:
zip :: forall a b f. Functor f => f a -> f b -> Tuple a b
zip = map2 Tuple
-- Likely needed to fill the gap between the seemingly-identical
-- (but actually different) `Tuple` and nested `Tuple2`.
zip2 :: forall a b f. Functor f => f a -> f b -> f (Tuple2 a b)
zip2 = map2 Tuple2
zip3 :: forall a b c f. Functor f => f a -> f b -> f c -> f (Tuple3 a b c)
zip3 = map3 Tuple3
...
zip10 :: ...
zip10 = map10 Tuple10
We probably need a different typeclass than Functor
though. What about Zippable
?
A motivation for adding these functions is to get closer to Elm's usability in this area:
https://package.elm-lang.org/packages/elm/core/latest/List#map2