What were the hurdles that you encountered?

One difficult aspect of Rust relative to Go must surely be generics and trait bounds. This is something it shares with Haskell and Scala. For people coming from those languages (like myself) the stack/heap thing is the most salient.

> What were the hurdles that you encountered?

> One difficult aspect of Rust relative to Go must surely be generics and trait bounds.

Conceptually this isn't bad at all. I understand the value and mechanism of specifying the required traits for types to a generic function. However, I just posted an example elsewhere in this discussion where there simply isn't a trait for the method I want to call. That was certainly a hurdle for me, and the workaround wasn't satisfying.

I mostly understand the semantics of borrowing mutable vs read-only references, and I'm pretty sure I understand the purpose and value of the concept. However, specifying lifetimes is completely different than any other language I've ever used, and I've used a couple dozen languages over several decades in my career. I haven't gotten past that hurdle yet.

> the stack/heap thing is the most salient.

I'll stick with my statement that I understand the stack and heap well enough (from a C or C++ point of view), but composing Box, Cell, Ref, RefCell, and friends is a non-trivial hurdle.

Theoretically yes, for a C/Assembly programmer you're aware of the difference between stack and heap allocated data, BUT the cognitive load is different because those languages don't differentiate them in a particular fashion, it's all just pointers and offsets at the end of the day. Rust on the other hand, because of the Box type makes it very explicit where exactly some piece of data lives. It's also relatively uncommon to stack allocate any kind of larger structure in C or assembly, almost by default that kind of thing is done in the heap, where Rust makes it really trivial (default even) to do so on the stack even though that's rarely the correct decision.

Depending on your background there probably are various hurdles to overcome in learning Rust, I'm not discounting that, but the most uniquely Rust one is the stack vs. heap issue, particularly since that combined with issues around shared state are the sources of most of the headaches you'll run into when fighting with the borrow checker. Pretty much every other feature of Rust is similar enough to another language that if you have experience elsewhere you won't find it particular troublesome. References are easy to understand if you know C/C++ (and to a lesser extent C#). The type system is easy to understand if you know Haskell or Scala (and to a lesser extent JavaScript/Python). The generics system is pretty much the same as Java, C#, Haskell, Scala, or C++ (and probably others).

Rust IS a complex language, but it also provides a unique feature set and has some fairly unique goals. IF you need or desire the features Rust provides, pretty much ONLY Rust is going to get you what you want. C, C++, or Assembly potentially can deliver the same functionality, although it's questionable whether their ergonomics will be better or worse than Rusts for a given task, and they almost certainly will be more bug and error prone. Rust lets you have all the fine grained performance tweaking (or just plain low level access) you can get with C/C++/Assembly, while also giving a strong peace of mind that your code is correct and error free. It's also arguably easier than C++ although that comparison is a bit Apples and Oranges, C++ has a great many years of tweaking and experimenting behind it so things like Boost go a long way towards providing something like a most optimal (from a ergonomics standpoint) C++ experience that ignores all the languages pitfalls and sandtraps. Rust on the other hand has just barely hit 1.0 and the community hasn't even discussed, let alone come to any kind of consensus on the best way to tackle various issues yet. Rust will get there in time, but it's still early in the process and it shows.

Bottom line, if you need the features Rust provides, but aren't comfortable with how young the language is and want more hand holding, C++ (or maybe C) is probably the language you want. This isn't to say Rust is a bad language or you shouldn't use it, I think learning and using a new language is reason enough and the certainty Rusts type system and borrow checker provide is a very strong argument in its favor, but you need to be aware of what you're signing up for when you make that decision.

> the most uniquely Rust [hurdle] is the stack vs. heap issue

I can only speak for myself, and I politely disagree. So far, explicit lifetimes (both the syntax and the concepts) seem like the most uniquely Rust issue.

> [if you] want more hand holding, C++ (or maybe C) is probably the language you want.

Heh, if you think C++ holds your hand, I'm not sure we're on the same page. What I know of C++ was hard-won after reading many books and fighting with the compiler for many years.

Sorry, it wasn't exactly clear from the context but by hand holding I meant more in terms of the resources available. C++ by its very nature has tons of great libraries, tools, and various kinds of documentation. If you can think of it, someone has most likely written a tutorial about how to do it in C++. Additionally there have been entire forests worth of books written about various facets of C++. Rust in contrast has few libraries, fewer tools, and little to no documentation for most of what it does have. This isn't to say Rust is bad, it's simply new and building up documentation takes time.