Reflection: Is a form of meta programming that allows you to extract information from data structure in runtime. 

Swift’s version of reflection enables us to iterate over, and read the values of, all the stored properties that a type has — whether that’s a struct, a class, or any other type — enabling a sort of meta programming that can enable us to write code that actually interacts with the code itself.

https://www.swiftbysundell.com/articles/reflection-in-swift/

There is a Mirror struct, if you call on an object, it will give you an idea if it is class, struct, enum, tuple. But it does not work on all types for example closures. If it can not tell you what the type is, it will return nil.

There is a child property which has label and values. You can recursively go through the properties of a data structure and be able to sort of go down in a tree and really to figure out everything that is going on.