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diff --git a/testsuite/tests/simplCore/should_compile/T18346/MiniLens.hs b/testsuite/tests/simplCore/should_compile/T18346/MiniLens.hs
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+{-# LANGUAGE RankNTypes #-}
+
+module MiniLens ((^.), Getting, Lens', lens, view) where
+
+import Data.Functor.Const (Const(..))
+
+type Lens s t a b = forall f. Functor f => (a -> f b) -> s -> f t
+
+type Lens' s a = Lens s s a a
+
+lens :: (s -> a) -> (s -> b -> t) -> Lens s t a b
+lens sa sbt afb s = sbt s <$> afb (sa s)
+{-# INLINE lens #-}
+
+type Getting r s a = (a -> Const r a) -> s -> Const r s
+
+view :: Getting a s a -> s -> a
+view l = getConst . l Const
+{-# INLINE view #-}
+
+(^.) :: s -> Getting a s a -> a
+s ^. l = getConst (l Const s)
+{-# INLINE (^.) #-}