小编Ted*_*Ted的帖子

scala> val x = mutable.MutableList[(Int, Int)]()
x: scala.collection.mutable.MutableList[(Int, Int)] = MutableList()

scala> x += (1, 2)
<console>:10: error: type mismatch;
found   : Int(1)
required: (Int, Int)
          x += (1, 2)
                ^