Flatten [Any] Array Swift

Question

Using this Stack Overflow question I have the following code.

let numbers = [1,[2,3]] as [Any]
var flattened = numbers.flatMap { $0 }
print(flattened) // [1,         


        

Answer 1

Here's an alternate implementation of @rmaddy's anyFlatten:

It can be most concisely written like so, but it's quite cryptic:

extension Array {
    func anyFlatten() -> [Any] {
        return self.flatMap{ ($0 as? [Any]).map{ $0.anyFlatten() } ?? [$0] }
    }
}

Here's a more reasonable implementation:

extension Array {
    func anyFlatten() -> [Any] {
        return self.flatMap{ element -> [Any] in
            if let elementAsArray = element as? [Any] { return elementAsArray.anyFlatten() }
            else { return [element] }
        }
    }
}