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Memory safety and safety is not "the whole point of Rust". It's a nice low-level language with proper sum types (!), neat sum-type approach to errors, proper an

Memory safety and safety is not "the whole point of Rust". It's a nice low-level language with proper sum types (!), neat sum-type approach to errors, proper and easy to use iterators and much else including nice tooling, dep management, very high standards in packages and docs overall, etc. C++ lacks in pretty much all of those, so memory-safety or no, personally I can't picture myself choosing to do C++ for low-level work at will these days. Unless it's too low-level like dpdk or gpu kernels. > the language is incredibly hard to learn Not really. A few months from zero and you'll be up and running, provided you have prior C++ experience (based on cases I've observed in teams I've worked in). Maybe not including async rust though. > it's impossible to implement any non-trivial data structures in safe rust ANY, really? Any examples? (Other than linked list or other self-dependent structures)

Const-me 2y ago
> a nice low-level language The usability is not great, too opinionated. For example, they have decided their strings are guaranteed to contain valid UTF-8. Many external components (like Linux kernel) don’t have these guarantees, so the Rust has another OsString type for them. I think Rust is the only language which does that. The rest of them are fine keeping invalid UTF8 / UTF16 in their strings. > proper and easy to use iterators C++/11 introduced range-based for loops, they make iterators very easy to use. > nice tooling Packages are OK I guess, but I think other classes of tools are lacking. For example, I can’t imagine working on any performance critical low-level code without a good sampling profiler. > ANY, really? Yes. Even very simple data structures like std::vec::Vec require unsafe code, they call unsafe APIs like alloc::alloc for memory management. This can, and did, cause security bugs: https://shnatsel.medium.com/how-rusts-standard-library-was-vulnerable-for-years-and-nobody-noticed-aebf0503c3d6 https://shnatsel.medium.com/how-rusts-standard-library-was-v... By comparison, modern C# is memory safe all the way down, possible to implement even very complicated data structures without a single line of unsafe code. The collection classes from the standard library don’t use unsafe code either.
- pcwalton 2y ago
  > I think Rust is the only language which does that. Python 3 strings are enforced valid Unicode (but not technically UTF-8, as they can contain unpaired surrogates). > Packages are OK I guess, but I think other classes of tools are lacking. For example, I can’t imagine working on any performance critical low-level code without a good sampling profiler. I've been using sampling profilers with Rust since before the language was publicly announced! > Yes. Even very simple data structures like std::vec::Vec require unsafe code, they call unsafe APIs like alloc::alloc for memory management. This can, and did, cause security bugs: This is yet another example of "Rust's liberal use of 'security bug' gives people the wrong impression". Although I wish they didn't, Rust users often use "security bug" to mean any memory safety problem in safe code. By this measure every C++ program in existence is a security bug. The question is whether any applications were exploitable because of this, and I don't know of any. > By comparison, modern C# is memory safe all the way down, possible to implement even very complicated data structures without a single line of unsafe code. Only because the runtime has hundreds of thousands of lines of unsafe code written in C++, including the garbage collector that makes it possible to write those collections.
- kelnos 2y ago
  > Even very simple data structures like std::vec::Vec require unsafe code, they call unsafe APIs like alloc::alloc for memory management. This can, and did, cause security bugs That's way better than everyone writing their own unsafe vec implementation in C or C++, and then having to deal with those same security bugs over and over and over. And I'm sure GNU's libstdc++, LLVM's libc++, and whatever Microsoft calls their C++ stdlib have had a laundry list of security bugs in their implementations of the fundamental data structures over time. Just they were found and fixed 20 years ago, in a time when the security issue du jour wasn't huge news like it is today. > By comparison, modern C# is memory safe all the way down, possible to implement even very complicated data structures without a single line of unsafe code You really can't compare a GC'd language to Rust (or C or C++), at least not without acknowledging the inherent tradeoffs being made. And obviously that C# runtime has a bunch of unsafe C/C++ underneath it that lets you do those things.
  - 2y ago

Const-me 2y ago

> a nice low-level language The usability is not great, too opinionated. For example, they have decided their strings are guaranteed to contain valid UTF-8. Many external components (like Linux kernel) don’t have these guarantees, so the Rust has another OsString type for them. I think Rust is the only language which does that. The rest of them are fine keeping invalid UTF8 / UTF16 in their strings. > proper and easy to use iterators C++/11 introduced range-based for loops, they make iterators very easy to use. > nice tooling Packages are OK I guess, but I think other classes of tools are lacking. For example, I can’t imagine working on any performance critical low-level code without a good sampling profiler. > ANY, really? Yes. Even very simple data structures like std::vec::Vec require unsafe code, they call unsafe APIs like alloc::alloc for memory management. This can, and did, cause security bugs: https://shnatsel.medium.com/how-rusts-standard-library-was-vulnerable-for-years-and-nobody-noticed-aebf0503c3d6 https://shnatsel.medium.com/how-rusts-standard-library-was-v... By comparison, modern C# is memory safe all the way down, possible to implement even very complicated data structures without a single line of unsafe code. The collection classes from the standard library don’t use unsafe code either.

pcwalton 2y ago
> I think Rust is the only language which does that. Python 3 strings are enforced valid Unicode (but not technically UTF-8, as they can contain unpaired surrogates). > Packages are OK I guess, but I think other classes of tools are lacking. For example, I can’t imagine working on any performance critical low-level code without a good sampling profiler. I've been using sampling profilers with Rust since before the language was publicly announced! > Yes. Even very simple data structures like std::vec::Vec require unsafe code, they call unsafe APIs like alloc::alloc for memory management. This can, and did, cause security bugs: This is yet another example of "Rust's liberal use of 'security bug' gives people the wrong impression". Although I wish they didn't, Rust users often use "security bug" to mean any memory safety problem in safe code. By this measure every C++ program in existence is a security bug. The question is whether any applications were exploitable because of this, and I don't know of any. > By comparison, modern C# is memory safe all the way down, possible to implement even very complicated data structures without a single line of unsafe code. Only because the runtime has hundreds of thousands of lines of unsafe code written in C++, including the garbage collector that makes it possible to write those collections.
kelnos 2y ago
> Even very simple data structures like std::vec::Vec require unsafe code, they call unsafe APIs like alloc::alloc for memory management. This can, and did, cause security bugs That's way better than everyone writing their own unsafe vec implementation in C or C++, and then having to deal with those same security bugs over and over and over. And I'm sure GNU's libstdc++, LLVM's libc++, and whatever Microsoft calls their C++ stdlib have had a laundry list of security bugs in their implementations of the fundamental data structures over time. Just they were found and fixed 20 years ago, in a time when the security issue du jour wasn't huge news like it is today. > By comparison, modern C# is memory safe all the way down, possible to implement even very complicated data structures without a single line of unsafe code You really can't compare a GC'd language to Rust (or C or C++), at least not without acknowledging the inherent tradeoffs being made. And obviously that C# runtime has a bunch of unsafe C/C++ underneath it that lets you do those things.
- 2y ago