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diff --git a/testsuite/tests/typecheck/testeq1/FakePrelude.hs b/testsuite/tests/typecheck/testeq1/FakePrelude.hs
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+++ b/testsuite/tests/typecheck/testeq1/FakePrelude.hs
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+{-# LANGUAGE MultiParamTypeClasses, FunctionalDependencies,
+             OverlappingInstances, UndecidableInstances #-}
+
+--
+-- Test case adopted from the HList library
+-- http://www.cwi.nl/~ralf/HList/
+--
+
+module FakePrelude where
+
+
+--
+-- Type-level Booleans; nothing weird
+--
+data HTrue; hTrue :: HTrue; hTrue = undefined
+data HFalse; hFalse :: HFalse; hFalse = undefined
+class HBool x; instance HBool HTrue; instance HBool HFalse
+instance Show HTrue where show _ = "HTrue"
+instance Show HFalse where show _ = "HFalse"
+
+
+--
+-- Type-level type equality
+--
+class HBool b => TypeEq x y b | x y -> b
+
+
+--
+-- Value-level incarnation; nothing too weird.
+-- Rely on lazy show for type-level Booleans
+--
+typeEq :: TypeEq t t' b => t -> t' -> b
+typeEq = undefined
+
+
+--
+-- Type-level cast
+--
+class TypeCast x y | x -> y, y -> x
+ where
+  typeCast :: x -> y