# Swift's array

Is there a reason that Swift array assignment is inconsistent (neither a reference nor a deep copy)?

cd 竟然不一樣，依照「範例 1」來推論，d 應該要是 [1, 2, 3, 42] 呀？

ef 竟然也不一樣，依照「範例 1」來推論，f 應該要是 [4, 5, 3] 呀？

For arrays, copying only takes place when you perform an action that has the potential to modify the length of the array. This includes appending, inserting, or removing items, or using a ranged subscript to replace a range of items in the array.