The protocol extension introduced in Swift 2.0 is certainly a powerful tool, meanwhile things are also becoming more complex. Alexandros Salazar has wrote a post “The Ghost of Swift Bugs Future” to discuss it. There is also a Flow Diagram made by Omar Abdelhafith which showing how the methods dispatch works in Swift.
In this post, I try to discover a little bit more in case there is an extension or a subclass.
Tested with Swift 2.1 & Xcode 7.2
First of all, let’s replay the conclusion of Alexandros.