HomoHKTRow.purs

Main.purs

module Main where

import Prelude

import Control.Monad.Eff.Console (log)
import TryPureScript (render, withConsole)
import Type.Row


class HomoHKTRow (rs :: RowList) (f :: Type -> Type)
instance allFoosNil :: HomoHKTRow Nil f
instance allFoosCons :: (HomoHKTRow t f) => HomoHKTRow (Cons l (f h) t) f


data Foo a = Foo a

class FooRecord a
instance foozA :: (RowToList r rl, HomoHKTRow rl Foo) => FooRecord (Record r)

allFoos :: forall r. FooRecord r => r -> Unit
allFoos _ = unit

-- or without the `FooRecord` class
allFoos' :: forall r rl.
  RowToList r rl =>
  HomoHKTRow rl Foo =>
  (Record r) -> Unit
allFoos' _ = unit

demo :: Unit
demo = allFoos { x: Foo 3, y: Foo "test" }