Re:C or C++ for my game engine?
by pcwalton on Monday January 18, 2016 @11:42AM
(#10925334)
> I think that Rust's safety features are over-marketed in my experience.
I agree with you in the sense that overfocusing on safety has led to things like Andrei's "bulging muscle" criticism, implying that Rust is especially lacking in high-level and metaprogramming features. Compared to C++ and D, it certainly does have a lower feature count in that area (although I'd argue that it's counterbalanced by the fact that Rust holds the line on strong typing for generics and hygiene for macros, whereas C++ and D don't). However, compared to most other languages Rust has very feature-rich generic programming and metaprogramming support. We're not talking "does not support generics" here; we're talking about the difference between the 95% and the 99% metaprogramming use cases. In the overall landscape of industry languages, even just having associated types makes Rust's generics system one of the most sophisticated out there. The only popular languages I can think of with more powerful generics are C++, D, Scala, and Haskell, and the first two sacrifice strong typing.
The main reason for the focus on safety is that it, combined with the lack of GC, is what actually makes Rust unique. Very few industry languages have any features unique to them, but the borrow checker is one such feature. C++ and Swift may get something like it in the future, but Rust has it now, and the entire language and ecosystem is designed around it (and the borrow checker is especially difficult to bolt on to an existing language, because it relies on strong aliasing guarantees). So it's natural that most people have focused on the zero-overhead safety when describing Rust--it's the most salient answer to the question "what can I do with Rust that I can't do with language X?"
I agree with you in the sense that overfocusing on safety has led to things like Andrei's "bulging muscle" criticism, implying that Rust is especially lacking in high-level and metaprogramming features. Compared to C++ and D, it certainly does have a lower feature count in that area (although I'd argue that it's counterbalanced by the fact that Rust holds the line on strong typing for generics and hygiene for macros, whereas C++ and D don't). However, compared to most other languages Rust has very feature-rich generic programming and metaprogramming support. We're not talking "does not support generics" here; we're talking about the difference between the 95% and the 99% metaprogramming use cases. In the overall landscape of industry languages, even just having associated types makes Rust's generics system one of the most sophisticated out there. The only popular languages I can think of with more powerful generics are C++, D, Scala, and Haskell, and the first two sacrifice strong typing.
The main reason for the focus on safety is that it, combined with the lack of GC, is what actually makes Rust unique. Very few industry languages have any features unique to them, but the borrow checker is one such feature. C++ and Swift may get something like it in the future, but Rust has it now, and the entire language and ecosystem is designed around it (and the borrow checker is especially difficult to bolt on to an existing language, because it relies on strong aliasing guarantees). So it's natural that most people have focused on the zero-overhead safety when describing Rust--it's the most salient answer to the question "what can I do with Rust that I can't do with language X?"