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-rw-r--r--libraries/base/Data/Functor/Compose.hs7
1 files changed, 1 insertions, 6 deletions
diff --git a/libraries/base/Data/Functor/Compose.hs b/libraries/base/Data/Functor/Compose.hs
index 225d16283b..d8369ebc05 100644
--- a/libraries/base/Data/Functor/Compose.hs
+++ b/libraries/base/Data/Functor/Compose.hs
@@ -3,7 +3,6 @@
{-# LANGUAGE GADTs #-}
{-# LANGUAGE PolyKinds #-}
{-# LANGUAGE ScopedTypeVariables #-}
-{-# LANGUAGE StandaloneKindSignatures #-}
{-# LANGUAGE Trustworthy #-}
{-# LANGUAGE TypeOperators #-}
-----------------------------------------------------------------------------
@@ -27,7 +26,6 @@ module Data.Functor.Compose (
import Data.Functor.Classes
-import Data.Kind (Type)
import Control.Applicative
import Data.Coerce (coerce)
import Data.Data (Data)
@@ -40,9 +38,6 @@ infixr 9 `Compose`
-- | Right-to-left composition of functors.
-- The composition of applicative functors is always applicative,
-- but the composition of monads is not always a monad.
---
--- Kinds `k2` and `k1` explicitly quantified since 4.15.0.0.
-type Compose :: forall k2 k1. (k2 -> Type) -> (k1 -> k2) -> (k1 -> Type)
newtype Compose f g a = Compose { getCompose :: f (g a) }
deriving ( Data -- ^ @since 4.9.0.0
, Generic -- ^ @since 4.9.0.0
@@ -131,7 +126,7 @@ instance (Alternative f, Applicative g) => Alternative (Compose f g) where
-- | The deduction (via generativity) that if @g x :~: g y@ then @x :~: y@.
--
-- @since 4.14.0.0
-instance TestEquality f => TestEquality (Compose f g) where
+instance (TestEquality f) => TestEquality (Compose f g) where
testEquality (Compose x) (Compose y) =
case testEquality x y of -- :: Maybe (g x :~: g y)
Just Refl -> Just Refl -- :: Maybe (x :~: y)