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Comment by whyever | Hacker News Reader

> Why would you think that Rust is "far simpler" than C++?

C++ as a language is a lot more complicated. It has a lot of features with weird corner cases that interact in unfortunate ways.

> And I wouldn't say that Rust's safer than Java either.

Depends on what you mean with safe. If you mean memory safe, then they are about as safe. Rust has fewer runtime failures due to concurrency and null pointers though.

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Not sure why the above comment is downvoted. The number of features in C++ isn't the root of the problem with C++. The real problem with C++ is that it both has a lot of features and that all of those features interact in subtle and surprising ways. Even if Rust had as many features as C++ (which it doesn't, not by a long shot; Rust is a medium-sized language like Python (though with a far less forgiving learning curve than Python)), one of the design philosophies of Rust is that features should interact in predictable ways, and if two features can't interact in predictable ways, then the compiler should do its damndest to prevent them from being used together and explain why.

The biggest issue is not how complicated it is, rather there is no good way to prevent people to write C in C++.

Rust also has features which interact in subtle and surprising ways. Generics and operator traits bumping into the "coherence" rules is my personal pet peave. I doubt any user would have predicted that interaction, and even though the compiler gives a detailed pointer to why, it's cold comfort.

Honestly, after hating C++ for years, trying to use Rust made me appreciate more about C++. I wish someone would make a language which took the best parts of both.

> even though the compiler gives a detailed pointer to why, it's cold comfort

We'll just have to agree to disagree, because having the compiler watch my back and preemptively guard against unforeseen pitfalls is about the warmest comfort I could ask for. :P

Generics and operator traits ought to be orthogonal and composable. Would you still be comforted if the compiler didn't let you mix for loops and arithmetic in one function? I mean, even if it gave you a detailed error message...

Ok then please prove that C++ is more complicated than Rust by listing which features of C++ are not available in Rust. It's nice that the compiler can tell me when I do something wrong, but I still have to know how to write it correctly in the first place. In Java it's more or less code and forget.

And yes, I meant memory safety.

The biggest ones people ask for are non-type templates, HKT, and sometimes move constructors.

Besides the (desirable) features already listed by someone else, here are a few others, some of which can have unfortunate interactions: implicit conversions, constructors, member initializer lists, inheritance, overloading, default arguments, capture lists, variadic templates.

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