What percentage of the Rust community is a professional C++ developer, either now or recently in the past? I was under the impression that "nearly all" was a fair estimate.
If that's true, does that mean that the C++ community itself is "typically wrong" about their language?
There is no "right" or "wrong" C++, there's also no single "C++ community". I'd say that C++ isn't even a programming language, it's more like a meta-language to build your own language.
Whether that's good or bad is up for discussion, but (a) it gives a lot of freedom, (b) it invites tinkering, (c) it wastes a massive amount of time when trying to communicate with C++ coders from other confessions, and (c) it makes it hard to integrate C++ libraries into C++ projects.
edit: confession => 'denomination' seems to be the correct English term
All (good) programming languages are like that. In general, any API, any library that you develop is a language. I agree that C++ provides powerful tools of abstraction that make these languages easier to use (compared to what can be accomplished in C or Go, for example).
I think the only other language with a similar feel is Scala. It's the programming language equivalent to Magic The Gathering: half the fun is just in the mechanics of it all
I think complexity of C++ is merely a (partial) reflection of complexity of programming. For example, move semantics that you have mentioned is not specific to C++, and I find it nice when a language offers an explicit formalism for it.
But we have both, and most of the folks doing comparisons with C++ do tend to be actual C++ devs (because if you're coming from Python or Ruby and haven't done C++ you really ... can't? compare with C++?). At least within the community folks pretty strongly care about misrepresenting other languages so if stuff is inaccurate it gets called out; and for most "rust vs foo" blog posts I've only rarely seen glaring mistakes a few times. Small mistakes are common but those are common to any kind of post.
I took the comment in the post as a bit of hyperbole and probably referring to subjective bits that Rust+C++ & only-C++ programmers tend to disagree on.
In general most of the vocal Rust folks who talk about C++ talk about C++ because they have lived it.
shrug
I still chuckle when randos make arguments like "C++ can't be parsed with an LALR parser", or "virtual functions are more expensive than function pointers", as if the former is the end of the world, and the latter is a checkmate that will suddenly make my knees week, arms heavy. There's code in my editor, and it's just spaghetti.
I'm not an expert on parsers but I don't think LALR parser can evaluate constexpr C++ functions which is required for parsing C++.
E.g. in the following code, expression `A<f()>::a * u` will parse either as a variable declaration (int* u) or a multiplication (5 * 5) depending on the value returned by constexpr function f:
template<bool b> class A {};
template<> struct A<true> { typedef int a; };
template<> struct A<false> { static const int a = 5; };
constexpr bool f() { return true; }
const int u = 5;
int main() { A<f()>::a * u; }
When people talk about "C++", they may mean:
- "C++ as it theoretically could be in when C++20 or so is used pervasively"
- "C++ as it can be when certain C++17 features are used pervasively"
- "C++ as it is often used in practice today"
(and this is still oversimplifying more nuanced realities).
It's very common for people to make observations about "C++" which are wrong on one sense and right in another.
Coming from the C++ world and being fairly knowledgeable about the language (not a full language lawyer but someone people usually turn to) and learning Rust, I find it rare for there to be bad comments from the Rust folks. I don't understand where this is coming from.
Now for my own judgemental comment. I see a trend of people in /r/cpp and other places ignoring the differences (like safety) or misrepresent Rust.
To be clear, I fully accept people having differences in priority (how much safety needs to be compiler-enforced). Its people who don't recognize the difference that I'm bothered by.
Rust is also foreign enough that a trivial glance can be misleading like assuming exceptions are the equivalent of panics because someone got caught up on them having a similar implementation (stack unwinding by default) when in reality, Result is more what people should look at (transport information, ?-operator for unwinding, etc).
[1] https://www.reddit.com/r/cpp/comments/75eqal/millennials_are...
Well, where they're right is in having a modest and non-condescending attitude, which is something that C++ pundits should consider adopting.
There are C++ experts who display modesty, just as there are members of the Rust community who display modesty. There is no need to try to retaliate against one person's words by hurling generalized insults against an entire group.