T10709.hs:6:21: error: [GHC-91028]
    • Couldn't match type ‘a2’
                     with ‘(forall a4. IO a4 -> IO a4) -> IO a3’
      Expected: a2 -> IO a3
        Actual: ((forall a. IO a -> IO a) -> IO a3) -> IO a3
      Cannot equate type variable ‘a2’
      with a type involving polytypes:
        (forall a4. IO a4 -> IO a4) -> IO a3
      ‘a2’ is a rigid type variable bound by
        the inferred type of x1 :: a2 -> IO [a3]
        at T10709.hs:6:1-24
    • In the second argument of ‘(.)’, namely ‘mask’
      In the expression: replicateM 2 . mask
      In an equation for ‘x1’: x1 = replicateM 2 . mask
    • Relevant bindings include
        x1 :: a2 -> IO [a3] (bound at T10709.hs:6:1)

T10709.hs:7:22: error: [GHC-91028]
    • Couldn't match type ‘a1’
                     with ‘(forall a2. IO a2 -> IO a2) -> IO a’
      Expected: a1 -> IO a
        Actual: ((forall a1. IO a1 -> IO a1) -> IO a) -> IO a
      Cannot instantiate unification variable ‘a1’
      with a type involving polytypes:
        (forall a2. IO a2 -> IO a2) -> IO a
    • In the second argument of ‘(.)’, namely ‘mask’
      In the expression: (replicateM 2 . mask) undefined
      In an equation for ‘x2’: x2 = (replicateM 2 . mask) undefined
    • Relevant bindings include x2 :: IO [a] (bound at T10709.hs:7:1)

T10709.hs:8:22: error: [GHC-91028]
    • Couldn't match type ‘a0’
                     with ‘(forall a2. IO a2 -> IO a2) -> IO a’
      Expected: a0 -> IO a
        Actual: ((forall a1. IO a1 -> IO a1) -> IO a) -> IO a
      Cannot instantiate unification variable ‘a0’
      with a type involving polytypes:
        (forall a2. IO a2 -> IO a2) -> IO a
    • In the second argument of ‘(.)’, namely ‘mask’
      In the first argument of ‘($)’, namely ‘(replicateM 2 . mask)’
      In the expression: (replicateM 2 . mask) $ undefined
    • Relevant bindings include x3 :: IO [a] (bound at T10709.hs:8:1)