Haskell-更多类型推理问题

getCount :: (Num a) => a -> [a]
getCount int = foldl 
       processOneCount 
       [0,0,0,0,0,0,0,0,0,0] 
       (map (singleDigitCount) (map (digitToInt) (show int)))

Couldn't match expected type `a' against inferred type `Int'
  `a' is a rigid type variable bound by
      the type signature for `getCount'
        at C:\Users\RCIX\Desktop\Haskell Code\test.hs:23:17
  Expected type: [a]
  Inferred type: [Int]
In the expression:
    foldl
      processOneCount
      [0, 0, 0, 0, ....]
      (map (singleDigitCount) (map (digitToInt) (show int)))
In the definition of `getCount':
    getCount int
               = foldl
                   processOneCount
                   [0, 0, 0, ....]
                   (map (singleDigitCount) (map (digitToInt) (show int)))

然而当我做一个 :t [0,0,0,0,0,0,0,0,0,0] 我回来了 [0,0,0,0,0,0,0,0,0,0] :: (Num t) => [t]