[kibwen]

Check out the high-level overview of Servo's design:

https://github.com/mozilla/servo/wiki/Design

The goal is extremely pervasive concurrency in aspects that no modern engine has yet begun to approach (and likely could not approach without enormous effort and/or a full-on rewrite).

[jerf]

You can drop the "likely". Retrofitting pervasive concurrency onto a sizable existing codebase is to a first approximation impossible. It makes merely trying to retrofit pervasive unit testing (hard, but "merely" a long mechanical slog) or correctness with string encoding a cake walk. "Impossible" here can be taken to read as "would require as much effort to do the retrofit as the rewrite would take".

[pkulak]

> Copy-on-write DOM. In Servo, the DOM is a versioned data structure that is shared between the content (JavaScript) task and the layout task, allowing layout to run even while scripts are reading and writing DOM nodes.

Wow

[shawn-butler]

>> Because C++ is poorly suited to preventing these problems,

It is really hard to take seriously any project that has this kind of nonsense in its introduction.

[steveklabnik]

I think you're being downvoted because if anyone knows about the pain of using C++ to develop a browser engine, it's Mozilla. They have some pretty strong empirical evidence to back up their statement.

[shawn-butler]

No, you don't bash a language for failures of the people using it. It is hyperbole unsupported by any evidence and it is precisely this mentality that keeps our profession on the Greatest New Thing(TM) every x years treadmill for better or worse.

Language bashing/trolling serves no purpose.

I am rather most likely being downvoted because HN in the past few months has taken an extreme downturn towards a slashdot/herd mentality, but that is just another pendulum swinging.

[acdha]

> I am rather most likely being downvoted because HN in the past few months has taken an extreme downturn towards a slashdot/herd mentality

You're being downvoted because you clearly have no idea what you're talking about. It's entirely appropriate to criticize a language for being too hard to use correctly - your argument would apply equally well to saying that C++ should never have been created because it was simply the fault of people using earlier languages not using them sufficiently well.

This approaches dark comedy because you're also criticizing a company which maintains one of the largest and most important codebases in existence and has a huge list of bugs and security issues demonstrating that even in the hands of very experienced developers it's too easy to use C++ incorrectly.

[shawn-butler]

Oh, so you think the statement that was quoted was that c++ was too hard to use? Because when you read what was actually quoted it says c++ is poorly suited to solve issues related to data races and parallelism which is a pretty false statement.

Are you able to see how that is different now with a little help? Or is it so insufficient to make up straw arguments and put words into my mouth that now you want to do the same for Mozilla foundation?

[kragen]

C++ is the only realistic option for some things, but it's not without serious problems. Intelligent criticism of a formal system, such as a programming language, is what allows us to make better ones in the future.

If you honestly think there's no point in trying to make better programming languages, you're welcome to continue programming in FORTRAN IV. But don't expect other people to take your opinion seriously about what "serves no purpose".

[shawn-butler]

Can you point to where I said any such thing?

The point was simple: language bashing/trolling is childish. It is hard to take seriously a project with that kind of statement in its introduction.

If instead it said Rust does X in order to achieve goal Y, that would be more useful.

[kragen]

"Language bashing" is merely a derogatory term for "language criticism". Language criticism is, as I said, a necessary foundation for designing better languages; if existing languages are flawless, then designing new ones would simply be part of "the Greatest New Thing(TM) every x years treadmill" that you referred to in your initial comment. On the other hand, if you can identify real problems in existing languages, then you have some hope of designing new languages that are actually better, not just newer. But you can't do that without "language bashing". Without "language bashing", we'd still be back at FORTRAN IV. And if that's what you want, you can probably live in FORTRAN-world.

"Trolling" is bullshitting to provoke a response; your accusation there, if we take you at your word, would have to be that the Rust developers are developing a new programming language as a sort of hoax in order to get a rise out of C++ programmers.

I don't think it really serves your point well to suggest that Graydon Hoare, Brian Anderson, Sebastian Sylvan, Samsung, and so on, are "childish" and "hard to take seriously" and dishonest, because that requires us to choose between taking Graydon and Samsung et al. seriously and taking you, Shawn Butler, seriously. This is a competition that will be hard for you to win. Perhaps instead you could find a way to couch your criticism (whatever it is) in a way that makes it easier to accept. As it is, only people who have a pre-existing hate for Graydon or Samsung will be inclined to accept your argument.

[nnethercote]

No, you're being downvoted because fine-grained parallel programming in C++ is really hard, but you're saying that it's not.

[shawn-butler]

Wow, I said what?

Also while I hate to be the harbinger of bad news, parallel programming in any language is Really Hard(tm) for most people. Personally, I think there's a fundamental disconnect in how human cognition perceives the world on the one hand and massive parallelism on the other at which very few people I have met really excel relative to the larger population.

[abraininavat]

Are you claiming that all languages are equally good for all purposes? Or are you claiming that C++ is in fact particularly well suited for parallel development and inherent avoidance of data races?

Coming from a C++ developer, I don't think you're well aware of its limitations. Do yourself a favor and learn a little bit of Rust. It'll open up your mind a little, and just might make you a better C++ programmer.

[shawn-butler]

The C++ memory model (which btw is what underlies any threading facility) was always sufficient for handling the complexity but it never offered any opinions or constraints on implementations until C++11; the standards committee wisely preferred to defer instead to the writers of libraries to provide appropriate designs and services tailored to the specific needs of user communities and particular operating system facilities.

I'm pretty sure based on your writing that you have little to offer me that I don't already understand about the language, but thanks for your hollow advice though. Here, I'll make an empty prediction in return: in 3 years you will be complaining about how difficult it is to do distributed parallelism in Rust and what absolute garbage it is compared to <insert name here>.

The point was simple but fanbois want straw men and windmills at which to tilt: if you have something you think is better, extol its virtues and provide comparative analysis instead of bashing/trolling what currently exists completely out of any useful context.

I really have little interest in discussing anything technical on HN anymore. Here's a token wikipedia link, that's what passes for knowledge I guess [0].

Also I would keep your "advice" to yourself. I certainly hope you wouldn't speak to people like that in person, and you definitely wouldn't be allowed to speak in such a fashion to me in particular. I am pretty familiar with Rust's evolving semantics and syntax, thanks.

[0] http://en.wikipedia.org/wiki/C%2B%2B11#Threading_facilities

[Symmetry]

I'm note sure exactly what you mean by "the C++ memory model" but I'm pretty sure that it does not underlie Rust's model of threading unless you just mean that Rust assumes a Von Neuman architecture. First of all the stacks of Rust threads are segmented, unlike those of C++ threads, so there's one feature that cannot be duplicated by a C++ library.

But more importantly, Rust doesn't allow any shared mutable state, meaning that all the synchronization primitives C++11 provides can be used by the language automatically by the language on your behalf. Of course, nothing prevents someone from creating a library in C++ that does the same thing, but there's no way for the compiler to enforce the clean thread-wise separation of state and if you've forgotten to get rid of some pointer to an object you're passing to another thread you won't know about it potentially until you're debugging it in production. Also there are a number of threading optimizations that the Rust compiler can make with re-ordering or eliding memory accesses that the C++ compiler can't.

[abraininavat]

You come off as whiny and immature, which is why your comments keep getting voted down. I have no doubt you're under the impression they are getting voted down because most people disagree with you, but you're wrong.

Out of curiosity, who wouldn't allow me to speak to you in such a fashion? Who's this imaginary authority who controls how I speak to children?

[eruditely]

This says more about you than the quality of the project.