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I have a UITableViewController that can display content from any of three different arrays. In Objective-C, what I would typically do is set a property on the TableVC that is a reference to the array to be displayed. Then the TableVC would not only be able to show the contents of that array, but also handle user-directed editing of the array, say, if they deleted or re-ordered elements.

The way it seems to work in Swift when I set a property on my TableVC to an array is that it is a copy of my model's array, not a reference. And while this is fine in certain contexts, in my application it seems bad for two reasons: 1) my arrays are enormous, thousands of elements, and copying huge arrays over and over again seems wasteful; 2) small edits are tougher to handle: I have to communicate back to the model about element deletion or re-ordering and make sure my view and model arrays stay in sync.

Setting a property that's a reference to an array is what I want to do, but there's no such thing as an inout object property in Swift.

What is the correct way for me to handle this?

Thanks.

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Swift Arrays are not actually copied every time you assign them; instead, they are copy-on-write. What this means is that the array is only copied when something mutates it; until that point, you only copy a reference, like with Objective-C.

With that said, if you need reference semantics, the NSArray class from Objective-C is still available in Swift. You can also create your own class type that wraps an Array if you prefer not to use the Objective-C bridge.

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