ListSwiftExample.swift

// ListSwiftAdapterDataSource.swift

public class Value {
    public let value: ListSwiftDiffable
    public let constructor: () -> ListSectionController

    public init<T>(value: T, constructor: @escaping () -> ListSwiftSectionController<T>) {
        self.value = value
        self.constructor = constructor
    }
}

public protocol ListSwiftAdapterDataSource: class {
    func values(adapter: ListSwiftAdapter) -> [ Value ]
}

// ViewController.swift

var values: [ListSwiftDiffable] = // ....

func values(adapter: ListSwiftAdapter) -> [Value] {
    return values.flatMap({ (value: Any) -> Value? in
        if let value = value as? Person {
            return Value(value: value, constructor: { PersonSectionController() })
        }
        return nil
    })
}