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swift - Are there any concrete examples when using the Any type is a good solution?

We all know that swift has a strong type system, and as such I lean towards using this system to my advantage :)

Here's what Apple has to say about using the Any type:

Type Casting for Any and AnyObject

Swift provides two special type aliases for working with non-specific types:

AnyObject can represent an instance of any class type. Any can represent an instance of any type at all, including function types. NOTE

Use Any and AnyObject only when you explicitly need the behavior and capabilities they provide. It is always better to be specific about the types you expect to work with in your code.

I don't know if it's me, but I kind of think the code starts to smell when using these (This maybe my lack of experience using them) - I know AnyObject is required/useful for interacting with Objective-C so I get that there is a practical nature to AnyObject's use.

So I wanted to know what concrete examples represent a good use of the Any type.

For example is it could be used to pass unknown content to a POST request constructor method where the method could safely use optional chaining to examine the unknown content.

Apple's example from the Swift Programming Language (Swift 2.2)

Any

Here’s an example of using Any to work with a mix of different types, including function types and non-class types. The example creates an array called things, which can store values of type Any:

var things = [Any]()

things.append(0)
things.append(0.0)
things.append(42)
things.append(3.14159)
things.append("hello")
things.append((3.0, 5.0))
things.append(Movie(name: "Ghostbusters", director: "Ivan Reitman"))
things.append({ (name: String) -> String in "Hello, (name)" })
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If you are using pure Swift (without the legacy Objective-C stuff) and you want an array where you can put Int(s), Bool(s) and String(s) then you need an array of Any.

let values: [Any] = [1, true, "I'm not a pointer!"]

enter image description here

But, wait I can also use an array of AnyObject right?

Nope. Infact Int, Bool and String in Swift are struct(s).

They why does this code compile?

enter image description here

The code above compile because the import Foundation does enable the bridge to Objective-C. This mean the Swift Int, Bool and String are allowed to be seen as objects by the compiler in order to preserve compatibility with Objective-C.

But as soon as you remove the import Foundation the code stop compiling.

enter image description here


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