Scala list concatenation，::: vs ++ - Scala list concatenation, ::: vs ++

問題：

Is there any difference between ::: and ++ for concatenating lists in Scala? 在Scala中連接列表的:::和++之間有什麼區別嗎？

scala> List(1,2,3) ++ List(4,5)
res0: List[Int] = List(1, 2, 3, 4, 5)

scala> List(1,2,3) ::: List(4,5)
res1: List[Int] = List(1, 2, 3, 4, 5)

scala> res0 == res1
res2: Boolean = true

From the documentation it looks like ++ is more general whereas ::: is List -specific. 從文檔中可以看出++更爲通用，而:::是List -specific。 Is the latter provided because it's used in other functional languages? 提供後者是因爲它用於其他功能語言嗎？

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解決方案：

參考一： https://en.stackoom.com/question/RWYO
參考二： https://stackoom.com/question/RWYO