Singletons/T124.hs:(0,0)-(0,0): Splicing declarations
    singletons
      [d| foo :: Bool -> ()
          foo True = ()
          foo False = () |]
  ======>
    foo :: Bool -> ()
    foo True = ()
    foo False = ()
    type FooSym0 :: (~>) Bool ()
    data FooSym0 :: (~>) Bool ()
      where
        FooSym0KindInference :: SameKind (Apply FooSym0 arg) (FooSym1 arg) =>
                                FooSym0 a0123456789876543210
    type instance Apply FooSym0 a0123456789876543210 = Foo a0123456789876543210
    instance SuppressUnusedWarnings FooSym0 where
      suppressUnusedWarnings = snd ((,) FooSym0KindInference ())
    type FooSym1 :: Bool -> ()
    type family FooSym1 (a0123456789876543210 :: Bool) :: () where
      FooSym1 a0123456789876543210 = Foo a0123456789876543210
    type Foo :: Bool -> ()
    type family Foo (a :: Bool) :: () where
      Foo 'True = Tuple0Sym0
      Foo 'False = Tuple0Sym0
    sFoo ::
      (forall (t :: Bool).
       Sing t -> Sing (Apply FooSym0 t :: ()) :: Type)
    sFoo STrue = STuple0
    sFoo SFalse = STuple0
    instance SingI (FooSym0 :: (~>) Bool ()) where
      sing = singFun1 @FooSym0 sFoo
Singletons/T124.hs:0:0:: Splicing expression
    sCases ''Bool [| b |] [| STuple0 |]
  ======>
    case b of
      SFalse -> STuple0
      STrue -> STuple0