It took a long time to write that engine and porting the whole thing properly also takes time. It just moves goalposts. Why didn’t he spend 80M on a new AAA game? If he spent any less than that, he certainly can’t draw any useful conclusions.
Have you ever looked over the codebase? It’s plenty large enough to draw useful conclusions from for most people let alone someone with his vast game experience.
Meanwhile, you are drawing bay conclusions with no credentials out evidence. As to actual games, setting aside the fact that Wolfenstein still sees play, loads of popular games are written in JS. Lots of others are in Java or C#. None of these make your case as Haskell, Ocaml, and StandardML (SML) are in the same performance range.
As to your argument about the efficiency of objects, what do you think functional languages use? Lets use SML as an example. There’s real arrays and they are also optionally mutable (yes, there’s linked lists too, but those can be used in C++ too).
Records are basically just C structs (they are immutable by default, but can contain refs which are mutable pointers). They can contain functions because functions are first class without the mess that many languages create.
You associate functions with datatypes which gives you the best part about methods. They also give you a kind of implicit interface too due to structural typing. I’d note that closures are mathematically equivalent to objects.
Finally, modules are everything a language like Java tries to get from classes (and more), but without any of the downsides of classes themselves.
People generally like the JS paradigm of factories and object literals (even if they hate the stuff like dynamic typing or type coercion). StandardML offers the same kinds of patterns, but with sound typing, simpler syntax without the warts, more powerful syntax, and performance in the same range as go or Java.
To me, your argument sounds like the people arguing that goto is better and more natural than looping constructs or the procedural guys arguing against OOP. I think if you messed around with StandardML, it would change your mind about what programming could be in the future.
Not only have I used SML, but I've also used F# and Scala extensively, both of which are well rooted in the ML philosophy. And for completeness, I've also used Common LISP, Haskell, Clojure, and Erlang.
Not once have I made an argument about the efficiency of objects oriented languages. Although that is important for performance wherever performance matters, it isn't my point in the slightest, and I already would agree with you that there are functional languages out there that are equivalent in performance.
My point is that the raw exposed complexity of functional state management (and especially pure functional state management) makes it worthless for game development. And until someone actually develops a real game, up to modern AAA standards using a functional language, all of your posturing is theoretical.
I can carry a pallet worth of goods to a supermarket using a pickup truck. It might be a little messy cause it can't pull up to a dock, so I'd have to unload it by hand instead of using a pallet jack, but the time I save by driving faster more than makes up for it. I could argue until I'm blue in the face about the theoretical benefits of using faster and more nimble pickups instead of slow and cumbersome lorries, but until someone actually builds a supermarket logistics network with them, those benefits are just theoretical. More importantly, the people who actually work in logistics industry would never attempt to do so because they can immediately see the problems with it.
So if you're that convinced your functional language would be better for game dev, then just do it already, cause nobody in the industry is gonna do it for you. I can guarantee it won't take long for you to understand what it is like when your paradigm choice puts you on the wrong side of the Expression Problem. And by the end of your experiment, you'll just be another crusty old insider that is too dumb and stuck in your ways to consider the amazing benefits of functional programming, just like what you're trying to do with me here.
What encapsulation exists in OOP or procedural code, but not in functions and modules?
The complexity in games is peanuts compared to any random business UI logic at whatever random company. Managing this complexity is an explicit reason to use functional paradigms. If OOP were better at managing complexity, why has everything been shifting from OOP to functional paradigms?
What about the functional approach makes it inferior at state management in your mind?
Nah, I'm not gonna write an essay just for some random dude on the internet. Try writing a game. Like a real one, not tic-tac-toe. You'll learn quickly enough.
An Entity Component System is literally the functional approach to programming under a different name and with mutation by default. There’s even been a huge move toward keeping ECS data classes separate from behaviors. At that point, it’s just a less ergonomic functional approach with better performance due to lower-level languages (though ATS or Rust are just as fast as C).
Maybe you’re thinking of FRP (functional reactive programming), but that isn’t even super mainstream among most functional programmers. I know some small games have used it, but it’s mostly used for specific kinds of UI in languages that enforce immutability and no side effects.
Have you ever looked over the codebase? It’s plenty large enough to draw useful conclusions from for most people let alone someone with his vast game experience.
https://github.com/id-Software/wolf3d/tree/master/WOLFSRC
Meanwhile, you are drawing bay conclusions with no credentials out evidence. As to actual games, setting aside the fact that Wolfenstein still sees play, loads of popular games are written in JS. Lots of others are in Java or C#. None of these make your case as Haskell, Ocaml, and StandardML (SML) are in the same performance range.
As to your argument about the efficiency of objects, what do you think functional languages use? Lets use SML as an example. There’s real arrays and they are also optionally mutable (yes, there’s linked lists too, but those can be used in C++ too).
Records are basically just C structs (they are immutable by default, but can contain refs which are mutable pointers). They can contain functions because functions are first class without the mess that many languages create.
You associate functions with datatypes which gives you the best part about methods. They also give you a kind of implicit interface too due to structural typing. I’d note that closures are mathematically equivalent to objects.
Finally, modules are everything a language like Java tries to get from classes (and more), but without any of the downsides of classes themselves.
People generally like the JS paradigm of factories and object literals (even if they hate the stuff like dynamic typing or type coercion). StandardML offers the same kinds of patterns, but with sound typing, simpler syntax without the warts, more powerful syntax, and performance in the same range as go or Java.
To me, your argument sounds like the people arguing that goto is better and more natural than looping constructs or the procedural guys arguing against OOP. I think if you messed around with StandardML, it would change your mind about what programming could be in the future.