add liftCompare & friends

[flip111]

Could a function like this be added? https://hackage.haskell.org/package/base-4.19.0.0/docs/Data-Functor-Classes.html#v:liftCompare

In which module should such function go?

[JordanMartinez]

What is f in the above context? Due to liftCompare lacking any type class constraints, how would you get the a or b out of f?

[flip111]

Does the class definition give sufficient information?

class (Eq1 f, forall a. Ord a => Ord (f a)) => Ord1 (f :: Type -> Type) where

Related
https://pursuit.purescript.org/packages/purescript-prelude/6.0.1/docs/Data.Ord#t:Ord1
https://pursuit.purescript.org/packages/purescript-prelude/6.0.1/docs/Data.Eq#t:Eq1

[JordanMartinez]

We don't yet support this syntax on the left side of the =>:

forall a. Ord a => Ord (f a)

How would we implement this?

[garyb]

How would we implement this?

Part of the purpose of Ord1 is to avoid that constraint, there's an Ord a constraint on compare1 instead.

[JordanMartinez]

Ok, I misread the Haskell docs. I thought liftCompare was a function, not a type class member... That explains a lot.