The Swift Reflection API and what you can do with it

Creating a Mirror

released Fri, 01 Mar 2019
Swift Version 5.0

Creating a Mirror

The easiest way of creating a mirror is the reflecting initializer:

public init(reflecting: Any)

Lets use it with our Bookmark struct:

let myMirror = Mirror(reflecting: aBookmark)


// prints : Mirror for Bookmark

So this creates a Mirror for Bookmark. As you can see, the type of the subject is Any. This is the most general type in Swift. Anything under the Swift Sun is at least of type Any 1. So this makes the mirror compatible with struct, class, enum, Tuple, Array, Dictionary, Set, etc.

There are three additional initializers in the Mirror struct, however those are mostly used for circumstances where you'd want to provide your own, custom mirror.


In particular, Any is an empty protocol and everything implicitly conforms to this protocol