BTW by the time of the rewrite, c++ will have memory safety mechanisms similar to rust: https://news.ycombinator.com/item?id=18037566
In particular, C++ has been engineered from the beginning to create expressive, powerful libraries, much moreso than Rust. The gap today is bigger than it was five years ago. This matters because every use of an idiomatic, powerful, mature library replaces code not using it that would have had bugs. Yes, Rust programs do have bugs.
Powerful is important in libraries because it translates to actually usable where you need it, without compromise. Any library you can't or don't use does you and your users no good.
Code that uses a good library will have none of the problematic, buggy constructs that Rust is supposed to protect you from.
Rust and C++ have different emphases. C++ has a huge head start, but also massive backward-compatibility anchors. It is certain that, over time, Rust will get better at expressing powerful libraries, but C++ is not sitting still.
It is very far from clear whether Rust will be important, ten years from now. It is far from clear that it is more beneficial to put resources into rewriting C things from scratch in Rust than to transition existing development from C to C++, and start replacing subsystems in-place.
What is clear is that the difference in benefit to starting any new project in Rust or in C++ is absolutely overwhelmed by the absolute benefit of starting in one of those, and not C.
No, I mean the stuff dang has already commented on.
You also did not explain the point in detail, you responded to what I said with a whole bunch of off-topic things, and then insinuated that I did not have the point.
The parent said that C++ would have "memory safety mechanisms similar to Rust," and my point was that while they are similar in some ways, they are not as comprehensive. That's an important distinction!
All of this other stuff you're talking about has nothing to do with that.
It was an honest question, and was not answered.
If you say that you mean it sincerely as a question and not as a swipe, I believe you. The problem is that lines like that are routinely used to take cheap shots at others, imply that they don't have a point, and so on. If that wasn't your intention, the burden is on you to disambiguate that by making clear that you're asking sincerely and making your question more specific.
I really can't fault Rust developers for choosing to put aside the whole C++ ABI mess by refraining from developing their own "Stable ABI" and sticking to the lowest common denominator of C FFI for the time being. And perceived ABI issues are the only thing that might stop you from building "expressive, powerful libraries" in the language. (Const generics and specialization are often-requested features that do impact this area, but they're in the pipeline already, and coming soon.)
This statement makes no sense. What stops you from building expressive, powerful libraries in Rust is the absolute lack of the corresponding features in the language that are necessary to the task.
No amount of testing and bug-fixing solves badly created software. Systemd is begging for a rewrite.
Now, I don't know if this one will be complete enough to replace the original. But yours is not a promising argument.
For a while it would ignore the system DNS settings, so it didn't only require it to be configured twice, but the systemd settings had an habit of changing in format every so often.
Udev failed a bit at the time it was being included on the package.
Oh, there was the time when the simple service launcher didn't conform to the documentation so a lot of daemons could fail to launch in unpredictable ways.
But the first I started using it was at the Debian migration. So the earlier bugs were all solved already.