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KindLinter.hs 2.12 KiB
{-# LANGUAGE AllowAmbiguousTypes #-}
{-# LANGUAGE ConstraintKinds #-}
{-# LANGUAGE DataKinds #-}
{-# LANGUAGE ExistentialQuantification #-}
{-# LANGUAGE KindSignatures #-}
{-# LANGUAGE PartialTypeSignatures #-}
{-# LANGUAGE PolyKinds #-}
{-# LANGUAGE RankNTypes #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TypeApplications #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE TypeOperators #-}
module KindLinter where
import Data.HList
import Data.Kind (Type)
import Data.Map.Strict
import Data.Void (Void)
import GHC.TypeLits (KnownSymbol, Symbol, symbolVal)
func :: a -> HList [Int, String]
func _ = hBuild 10 "test"
field :: forall a. KnownSymbol a => Label a
field = Label
data Linter a = Some a | None
type LintSingleton b a = Tagged b a
-- newtype LintSet a :: Record '[LintSingleton Int]
-- newtype LintSet (a :: Type -> Record '[Type]) = Record (a Void)
type SomeList (a :: Type) = Record '[Tagged "test" a]
type family MkList (b :: [Symbol]) a where
MkList '[] _ = '[]
MkList (x:xs) a = Tagged x a : MkList xs a
type Lints labels a = Record (MkList labels a)
type KnownProperties = '["hello", "test"]
record :: Lints KnownProperties Int
record =
Label @"hello" .=. 20 .*.
Label @"test" .=. 10 .*.
-- field @"x" .=. 20 .*.
emptyRecord
class KnownList a where
listVal :: Proxy a -> [String]
instance KnownList '[] where
listVal _ = []
instance (KnownList xs, KnownSymbol x) => KnownList (x:xs) where
listVal _ = symbolVal (Proxy @x) : listVal (Proxy @xs)
lints :: [String]
lints = listVal (Proxy @KnownProperties)
-- TODO: how to pattern match on that?
doSth :: forall a b ctxt. (KnownList a, b ~ MkList a (Linter ctxt)) => Proxy b -> String -> Linter ctxt
doSth _ name = None -- want to get a different result for each value of name in a
-- is there a better way than using listVal / something related to it?