[pron]

> That's a strange vision of the burden of proof.

I don't think so, because I don't think I'm claiming what you think I am.

> Anyway, complexity can come from many factors:

I completely agree, but I'm only talking about language complexity, in the strict syntactic, linguistic sense. I am not saying that all things considered, Rust makes maintaining programs harder than other languages -- nobody knows that until we have some empirical study -- but linguistic complexity is one very prominent property of Rust, as is, say, the memory safety of safe Rust, which, similarly, does not mean that Rust programs are overall safer than those written in, say, Zig, when all things are considered, because correctness also has many contributors, not just sound syntactic guarantees. There, too, only empirical study can settle the issue.

But you can't have it both ways, focusing on one specific piece when it comes to correctness yet insist on looking at the full picture only when it comes to complexity. All you can say is that, linguistically/syntactically, Rust offers some sound guarantees re memory safety and that it is complex, and that overall, both subjects are complex, involve many aspects, and require empirical study to make any definitive claim about.

> This is a stupid metric, because it confuses implementation complexity with user-facing complexity

It is obviously not stupid because it is commonly and usefully employed in computer science. But as with any precise definitions, it focuses on some aspects and not others. It captures the intrinsic difficulty of answering a question about a program. You are correct that it does not take into account human ergonomics and psychological aspects, but it is one more useful metric, even if not comprehensive.

> This argument is pretty similar to the Rust point of “when you get used to it, ownership doesn't adds any cognitive burden”,

Absolutely not (and, BTW, I was not referring just to ownership and lifetime when I spoke of Rust's complexity). It is a very precise and well defined property of Zig. The semantics of a Zig program, i.e. what it does in terms of what action it computes, is completely independent of comptime. It is not an ergonomic or psychological argument. comptime does not change the meaning of anything, and not only do you not need to figure out what happens at compile time and what happens at runtime -- unless you want to reason about efficiency -- but that knowledge contributes nothing. It's a meaningless distinction when it comes to semantics. It's a very powerful, well thought-out, theoretical and practical aspect of Zig's design.

[littlestymaar]

> but I'm only talking about language complexity, in the strict syntactic, linguistic sense.

Then again, on the strict syntactic sense, Rust is even less complex than C, because of the “most vexing parse” issue. If you wanted a rigorous analysis of the syntactic complexity, you could attempt to measure how difficult it is to write a lexer and a parser for every popular languages, and see how Rust performs. But given that the language grammar has been designed with parsing complexity in mind and have benefited from the hindsight of others before it, you'd be terribly disappointed.

From this discussion, and many of your previous interventions on this forum, it's pretty clear, even though the reason isn't, that you have developed a resentment towards Rust and you can't help bashing it.

Rust isn't a silver bullet, it has a fairly tough learning curve and as it tries to push the frontier of system programming language forward, it will take a few decisions that will ultimately be regarded as dead ends, and I have no doubt that future languages will avoids these pitfalls and provide improvement over the state of the art.

In the meantime, spreading your hate with unsubstantiated judgements like “Rust is one of the 5 most complex programming language ever” or “Rust harm code reviews” isn't really constructive for anyone.

Zig is a cool motorbike, Rust is a SUV. Arguing that your bike can indeed be safer than a SUV because you have more visibility and agility to avoid the danger is beyond childish.

Super easy cross compilation and incredible development velocity on small-medium projects are super cool features of Zig, and Rust can't beat that. No need to downplay the importance of Rust for the software industry (and as a friendly reminder, Rust is making its way to the Linux kernel, with the approval of Linus because unlike C++ or Ada isn't too complex to his taste ;).

[pron]

> can't help bashing it.

Perhaps this may disappoint you, but I -- like many and perhaps most developers -- don't get such emotional responses, positive or negative to any programming language [1], which might appear as resentment to the emotionally attached. I am very impressed with some aspects of Rust, less impressed with others, and overall, my feelings toward it overall are shaped just like yours: by personal aesthetics. I don't find Rust's aesthetics very appealing and so Rust isn't my cup of tea (although I would't resent working in it because I'm not emotional toward languages and I currently program mostly in a language whose aesthetics I like even less than Rust's [2]), while you find them appealing and so you do like Rust. It's all just a matter of taste, and I fully accept that not everyone shares mine. I think your approach is too coloured by emotion, and is therefore unconstructive. You're a zealot, and you project that attitude on others, so "unconvinced" appears to you as a personal attack, and scepticism or dislike seems to you like bashing.

> Rust is even less complex than C, because of the “most vexing parse” issue. If you wanted a rigorous analysis of the syntactic complexity, you could attempt to measure how difficult it is to write a lexer and a parser for every popular languages, and see how Rust performs

No. The complexity of a formal language, like that of any set, is the computational complexity of deciding whether a string is in the language (so, including type-checking), not as the complexity of the parsing phase (https://en.wikipedia.org/wiki/Computational_complexity_theor...). I'm not saying this is the most useful way to talk about language complexity in this context (and caveats are needed, anyway, to make a more fine distinction between languages), but that is certainly one well-known way to talk about the intrinsic complexity of a language.

> Zig is a cool motorbike, Rust is a SUV. Arguing that your bike can indeed be safer than a SUV because you have more visibility and agility to avoid the danger is beyond childish.

It is beyond childish to make such inane statements about software correctness when you're clearly not very familiar with the subject, and are drawn to arguments like "more correctness => more soundness". The effect of language design on correctness is a complex subject with mostly unsatisfying answers, and even in software verification research, the debate over the value of soundness is far from settled (and not currently leaning toward more soundness). An equally inane statement would be, "Zig is like a modern aeroplane, relying on multiple levels of safety, some mechanical and some human, while Rust is like an old train that breaks down and kills everyone once there's a problem with the tracks." If we've learned anything about software correctness in the past decade it's that there is not much we can assume in advance, and that we don't really know one best way to improve it. It is true that some researchers think that the best answer to any correctness issue is more soundness in the language, but not only is this not a consensus opinion, I doubt it's even a majority opinion.

[1]: I would say I'm a "language sceptic." I'm generally sceptical toward any empirical claim about the bottom-line effectiveness of linguistic features without empirical support, and overall think that whatever empirical studies we do have show little impact overall to language design (comparing "reasonable" alternatives, at least), certainly compared to what all language fans claim. I would never, say, make a definitive claim like, "Zig yields more correct programs than Rust", or "Rust yields more correct programs than Zig," without clear empirical support (and my guess based on prior results would be that they're about the same).

[2]: C++

[littlestymaar]

> I think your approach is too coloured by emotion, and is therefore unconstructive.

Your little “I'm a rational agent, you are too emotional” is pretty cute. But it would work better if your whole attitude in this thread didn't contradicted it, don't you think? “Rust is among the five most complex language” is not a rational argument, it's a personal feeling. Why you feel the need to spread your feelings over the internet while pretending you're not an “emotional” person is quite intriguing. If you want to look more like a rational person (no human really is), try to keep as much personal and unsubstantiated judgement out of your writings.

“Rust marketing makes safety claims that we should not take at face values” is alright, “Rust is one of the five most complex language ever” doesn't pass this test.

> is the computational complexity of deciding whether a string is in the language (so, including type-checking)

But for both Rust, C, Zig, and many others, it's undecidable, so by this definition of complexity, these language are definitely too complex (and equally so).[1] In fact, your desperate attempt to save your initial argument about complexity, by narrowing it to a tiny technical corner makes me cringe a bit.

> I would never, say, make a definitive claim like, "Zig yields more correct programs than Rust", or "Rust yields more correct programs than Zig," without clear empirical support (and my guess based on prior results would be that they're about the same).

The technicality of what constitute a “definitive claim” in a human to human conversation is an interesting question, but in practice truisms like “we can't conclude whether Rust is safer than C” or “we can't conclude that Rust doesn't bring more bugs than Zig does” aren't neutral: what such claim attempts to do is insinuate the opposite. And when combined with gratuitous judgements like “Rust is one of the 5 most complex language ever”, it looks a lot like an attempt to deter people from using this language you don't like. (And now I have a clue on what the root cause of your bad feelings can be).

[1] And as I said earlier, in the case of Zig and unsafe Rust and it's not just about type-checking: because of UB, even after compilation whether the compiled binary is the binary of a valid program or not is also undecidable.

[pron]

> But for both Rust, C, Zig, and many others, it's undecidable, so by this definition of complexity, these language are definitely too complex (and equally so)

My comments on this tried to be as careful and as precise as possible, and touched on this very issue.

> In fact, your desperate attempt to save your initial argument about complexity, by narrowing it to a tiny technical corner makes me cringe a bit.

Your emotional response here is so powerful that I think we're conversing on entirely different levels. I am sorry if my mild and careful statements have touched on something that you clearly see as essential to your identity.

> aren't neutral: what such claim attempts to do is insinuate the opposite

No. It is the most precise and careful statement that I can say, having followed the research for years and being a practitioner and advocate of formal formal methods. Anything I say, the more careful I try to be, it just seems to send you into further rage (and abuse). I think you're in a middle of a tantrum that's clouded your judgment, or perhaps, being a zealot, you cannot imagine any other attitude. Anyway, this conversation is making me very uncomfortable, as I sense you're in a very agitated emotional state, and I want no part of that.

[littlestymaar]

> No. I think you're in a middle of a tantrum and that's clouded your judgment.

I have to admit, this is cool rage-quit punchline!

Edit:

> I am sorry if my mild and careful statements have touched on something that you clearly see as essential to your identity, but I simply see no way to discuss this subject with you.

> Anyway, this conversation is making me very uncomfortable, as I sense you're in a very agitated emotional state, and I want no part of that.

Wow, it got even better as I refreshed the page!