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Comment by spacelizard | Hacker News Reader

I have too but I don't see any magic in Rust's borrowing beyond what you would get with using shared_ptr, weak_ptr and move semantics in C++11. Yeah there is a certain class of errors that the Rust compiler will check that will still give you a segfault in C++. But it doesn't get around the programmer still needing to have a firm understanding of RAII and the difference between the stack and heap in order to be effective in either Rust or C++, or Golang, or C99, or what have you.

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Rust is actually much closer to unique_ptr than shared_ptr or weak_ptr. The use of Rc is pretty small in practice.

The thing is that even with unique_ptr I can easily reach in via get() and I've broken the shared mutable state contract. It's trivial for me to trace what modifies things in Rust, I just follow the 'mut' annotations and since only one thing can hold it at a time it's very straightforward.

Rust also has one the best package managers I've seen. Union types which are the best way to represent states and state machines bar none. An iterator class that's the best I've seen(seriously has anyone actually used <algorithm>? How man begin/end pairs do I need?).

Plus the community is super-welcoming, there's more reasons but those are my top ones right now.

>But it doesn't get around the programmer still needing to have a firm understanding of RAII and the difference between the stack and heap in order to be effective in either Rust or C++, or Golang, or C99, or what have you

Who said it does? And why would it have to?

It'a just about catching those "certain class of errors that the Rust compiler will check that will still give you a segfault in C++".

Plus a nicer looking language, with a more modern design.

The more strict static checking in Rust means that the compiler can actually be a teaching tool for concepts like RAII and the heap/stack difference: it flags and explains places where the programmer is doing that doesn't make sense in those settings. A lot of effort has been put into the compiler diagnostics to make this compiler-is-a-teacher concept a reality.

The magic is that there is no way to enforce that in modern C++, in spite of current attempts.

There will always be that compiler or team that doesn't have any kind of reviews, static analysis, making use of binary libraries or legacy code.

Hence why safety at language level is much better than third party tooling, as tools can be ignored.

For one, additional safety. Rust's equivalent are more safe. Secondly, speed. Rust has several advantages: with shared_ptr, for example, you have the Rc/Arc split, the decreased number of refcount bumps, etc. (some of that speed comes from the safety, even...)

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