If people think C++ is hard to learn and attracts opinionated people boy are they in for a surprise when they start using Rust.
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Learning rust is like cycling over 2 big hills. It’s exhausting and painful if you’re in any way out of shape.
Learning C++ is like cycling from SF to LA. It starts easy enough and every day you’re making a lot of satisfying progress. But you have so far to go because of all the features and quirks of the language.
It’s probably easier to get started learning C++. But it’s also much faster to finish learning rust and be able to read almost all rust code. (Pin still scares me though)
You forgot to mention that someone mined parts of the roads from SF to LA.
More like NY to SF. The Appalachians would be when you're first learning pointers and the Rockies would be about the time you hit the STL and friends.
Having cut my teeth in Z80 Assembly, I could never understand people's aversion to pointers. You cannot do anything of any practical use, on hardware, without them.
You have to learn pointers in Rust too and I don't think the STL is any more complicated than Rust's standard library.
Regular Rust code uses references almost exclusively. (Unless you're working in kernel space or building fancy data structures.)
The big difference between C++ and Rust is what happens when you get something wrong. C++ has lots of undefined behavior and nasty surprises for the unwary. (I led a C++ project for a decade and saw it all.) In Rust, if you get something wrong, the compiler typically refuses to compile it. Which is also very frustrating, but the frustration is all up front.
It would also be easy to get started learning Rust, if people cared enough about doing it. The best way to learn Rust as a first programming language is to start with pure value-oriented programming at first, liberally using .clone() when necessary. Then introduce borrowing, with shared and mutable references; continuing with features involving interior mutability (Cell, RefCell etc.).
This is admittedly quite different from the way people usually learn C++, but it makes sense on its own terms. It's much closer to how higher-level languages like ML and Haskell are taught, and people have successfully learned those languages in introductory programming courses.
I like you're analogy, but I do think there are features of c++ that are big hills as well. To me it would be SF to LA with some big ups and downs on that long ride.
I'm also curious what's difficult about pin in rust? It basically just disables moving of the object for the lifetime of the pin.
> I'm also curious what's difficult about pin in rust?
I understand the concept. It’s the syntax which trips me up. You don’t mark structs as Pin. You mark them as !Unpin. And then, when is it safe to pin_project fields? Every time I read the documentation I understand it for about an hour. 2 weeks later I need to re-read the docs again to convince myself I’m not subtly messing anything up.
I’ve also gotten myself in hot water writing custom Futures, trying to wade through the barrage of compiler errors at the intersection of lifetimes, Pin and async. It’s a lot harder than it needs to be. The compiler holes around GAT, async closures and async trait methods doesn’t help.
I like the analogy!
I’m still not comfortable with Pin, UnsafeCell, raw FFI (lifetime and ownership handling across the boundary is tricky), and complex macros. But I also think that you don’t need to understand these at all to be an effective Rust dev.
rust doesn't have many of the features of c++, so it seems easier until you realize it's not.
Rust is way easier to learn than C++.
Until one needs to deal with async/await, write GUI code, the upcoming GAT, or macros.
Except that the C++ substitutes for those features (where applicable; C++ has nothing like GAT, and has to make do with complex template meta-programming) are a lot harder too.
C++ has had GAT like capabilities on templates since forever.
Complex template meta-programming only if one is stuck in pre-C++17 compilers.
Microsoft has apparently ported DWrite to Rust (the C++/WinRT team is now having all the fun in Rust/WinRT, while ignoring the lack of tooling in C++/WinRT after they killed C++/CX), Azure IoT unit is adopting Rust on Azure Sphere alongside C while not supporting C++, and at Ignite Mark Russinovich did mention they are planning to port some sysinternals tools into Rust as kind of POC.