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611 points LorenDB | 3 comments | | HN request time: 0.836s | source
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dvratil ◴[] No.43908097[source]
The one thing that sold me on Rust (going from C++) was that there is a single way errors are propagated: the Result type. No need to bother with exceptions, functions returning bool, functions returning 0 on success, functions returning 0 on error, functions returning -1 on error, functions returning negative errno on error, functions taking optional pointer to bool to indicate error (optionally), functions taking reference to std::error_code to set an error (and having an overload with the same name that throws an exception on error if you forget to pass the std::error_code)...I understand there's 30 years of history, but it still is annoying, that even the standard library is not consistent (or striving for consistency).

Then you top it on with `?` shortcut and the functional interface of Result and suddenly error handling becomes fun and easy to deal with, rather than just "return false" with a "TODO: figure out error handling".

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jeroenhd ◴[] No.43908294[source]
The result type does make for some great API design, but SerenityOS shows that this same paradigm also works fine in C++. That includes something similar to the ? operator, though it's closer to a raw function call.

SerenityOS is the first functional OS (as in "boots on actual hardware and has a GUI") I've seen that dares question the 1970s int main() using modern C++ constructs instead, and the API is simply a lot better.

I can imagine someone writing a better standard library for C++ that works a whole lot like Rust's standard library does. Begone with the archaic integer types, make use of the power your language offers!

If we're comparing C++ and Rust, I think the ease of use of enum classes/structs is probably a bigger difference. You can get pretty close, but Rust avoids a lot of boilerplate that makes them quite usable, especially when combined with the match keyword.

I think c++, the language, is ready for the modern world. However, c++, the community, seems to be struck at least 20 years in the past.

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jll29 ◴[] No.43911784[source]
> I think c++, the language, is ready for the modern world. However, c++, the community, seems to be struck at least 20 years in the past.

Good point. A language that gets updated by adding a lot of features is DIVERGING from a community that has mostly people that still use a lot of the C baggage in C++, and only a few folks that use a lot of template abstraction at the other end of the spectrum.

Since in larger systems, you will want to re-use a lot of code via open source libraries, one is inevitably stuck in not just one past, but several versions of older C++, depending on when the code to be re-used was written, what C++ standard was stable enough then, and whether or not the author adopted what part of it.

Not to speak of paradigm choice to be made (object oriented versus functional versus generic programmic w/ templates).

It's easier to have, like Rust offers it, a single way of doing things properly. (But what I miss in Rust is a single streamlined standard library - organized class library - like Java has had it from early days on, it instead feels like "a pile of crates").

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1. mgaunard ◴[] No.43913243[source]
A lot of people using C++ don't actually use any libraries. I've observed the opposite with Rust.

People choose C++ because it's a flexible language that lets you do whatever you want. Meanwhile Rust is a constrained and opinionated thing that only works if you do things "the right way".

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2. tialaramex ◴[] No.43913436[source]
> People choose C++ because it's a flexible language that lets you do whatever you want.

You went on a bit too long. C++ lets you do whatever. Whether you wanted that is not its concern. That's handily illustrated in Matt Godbolt's talk - you provided a floating point value but that's inappropriate? Whatever. Negative values for unsigned? Whatever.

This has terrible ergonomics and the consequences were entirely predictable.

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3. mgaunard ◴[] No.43921379[source]
It's just strong typing. You can do it in C++ too.