I agree. I never worked with swift and had to look up the terminology. Most of what the article refers to maps to terms from C++ (which is already horribly complicated and offers way too many ways to shoot yourself in the foot) or Java. That PWT sounds an awful lot like a vtable. In C++ you mess up by forgetting to add "virtual" (luckily we recently got "override"), but it seems swift's protocols add another dimension to make it possible to mess up in.
It's weird how people preach over and over how arcane and cumbersome old languages like C(++) are, with the neckbeards defending it with "well you just have to adhere to this list of best practices and it's absolutely fine", and then when some new and hip language comes along and offers just as many traps, the same people giving the "old languages" crap suddenly go all "well it's bad design to do that! Just adhere to this list of best practices here..."
As someone who transitioned from Java to C#/.Net to Objective-C and finally to Swift, AMEN TO THAT!
I learned not to say anything as apparently every software engineer "generation" needs to follow something "hip" when very young. Some will grow to see the cycle as it repeats itself in front of them, others will die believing "my programming language was the best, you just had to stick to this list of best practices".
Also, "bad design" quite often means "not the way I'm used to and feel comfortable with".
There's an element of this even within the community of a single language, too. E.g., Apple's been doing Swift talks at WWDC where they sort of introduce their blow-your-mind-paradigm-of-the-year: "Protocol Oriented Programming" was two years ago; "Embrace Algorithms (subtitle: delete your for loops)" was this year.
It concerns me because these are such lush, ripe targets for cargoculting. The behavior in this article is problematic exactly because of the "Apple says we must not use inheritance for anything! I can just use a protocol extension; that's totally not inheritance" mindset.
It's weird how people preach over and over how arcane and cumbersome old languages like C(++) are, with the neckbeards defending it with "well you just have to adhere to this list of best practices and it's absolutely fine", and then when some new and hip language comes along and offers just as many traps, the same people giving the "old languages" crap suddenly go all "well it's bad design to do that! Just adhere to this list of best practices here..."