hedgeDiff blo bhi t (Bin _ x l r) = merge (hedgeDiff blo bmi (trim blo bmi t) l)
                                          (hedgeDiff bmi bhi (trim bmi bhi t) r)
  where bmi = JustS x
#if __GLASGOW_HASKELL__ >= 700

hedgeDiff blo bhi t (Bin _ x l r) = merge (hedgeDiff blo bmi (trim blo bmi t) l)
                                          (hedgeDiff bmi bhi (trim bmi bhi t) r)
  where bmi = JustS x
#if __GLASGOW_HASKELL__ >= 700

hedgeDiff blo bhi t (Bin _ x l r) = merge (hedgeDiff blo bmi (trim blo bmi t) l)
                                          (hedgeDiff bmi bhi (trim bmi bhi t) r)
  where bmi = JustS x
#if __GLASGOW_HASKELL__ >= 700
