Graphs (and trees - their special case) are data structures used in modeling complex problems such as finding an optimal route, exploring possible moves in a game, caching engines, modeling relations and more . That’s why they are very often the fundament of software engineer interview tasks in big companies - FAANG. Let’s implement some basic graph algorithms in Rust.

Rust - single ownership and self reference

Rust is a great programming language that achieves memory safety by forcing a single ownership model and borrow-checker mechanism. That is actually problematic for data structures that require referencing Self type e.g. graphs, trees, and double-linked lists. So it is impossible in Rust to express this:

One of the features I love in Rust is very explicit copying. Every potentially expensive copy (clone) is clearly visible and can be easily caught during code review even though a small piece of code has been changed. That is probably one of the biggest advantages of Rust over C++. Nevertheless, more experienced Rust programmers know that it is not always easy to judge if some clone is expensive or not. In this article, I would like to present Facebook’s solution for that problem - Dupe trait from Gazeebo crate .

Carbon, a new programming language by Google that was announced at CppNorth 2022 conference as part of the presentation “Carbon Language: An experimental successor to C++” by Chandler Carruth on July 22nd 2022 (link ). The news spread quickly over the Internet and a few friends reach out to me to ask about my opinion about it and if Rust is going to die because of the appearance of a new baby of a big player in this industry. Well, Rust is doing fine and I will summarize my thoughts about Rust, Carbon, and modern C++ (C++20 standard as of today).

I’m a huge Rust enthusiast and you can read more about it in my previous article . Today, I’m gonna show you 2 examples of how Rust can be used together with some existing C and C++ codebases. Rust was designed with its FFI (Foreign Function Interface) in mind so it allows cheap (or even zero cost) interoperability with C and C++. For both solutions (plain C and C++), I’ll demonstrate that we can call C/C++ and Rust code back and forth (pass Rust callback to C++ code). I’ll focus on performance, flexibility, and limitations too.

Recently, I had the pleasure challenge to install Ubuntu on a new laptop. After installation, I noticed that there is no WiFi option available. Farther diagnosis with ifconfig showed that there was no network card supporting wifi. Moreover, the laptop was “too new” to have an old-school Ethernet socket…

Flashback

A few years ago I had a similar problem. In short, the company I joined bought me the perfect new Dell laptop. The problem was that they told me to install an older Ubuntu LTS that didn’t have a WiFi driver for such new hardware. Fortunately, I also had an Ethernet socket so I could work in the old school way. Later, I downloaded the new driver’s source code and compiled it so eventually, I could use WiFi too. The problem never appeared again once I updated to newer Ubuntu LTE with a much newer kernel.

Usually, I’m skeptical about new technologies and programming languages. I take every novelty with a pinch of salt. Not because of the steep learning curve and lack of time but because I saw too many examples where promises were not delivered. The majority of the new technologies provided only minor improvements which were not really worth migration time.

When I heard about Rust for the first time, my feelings were the same: if you need strongly typed high-performance native language without GC, why not just modern C++11 (or newer) instead of a new language? Is it really worth creating a new language instead of providing a C++ library that can be added to existing projects? A few months ago, I finally dived deeper into Rust and started writing some code in it. Rust extremely positively surprised me and become my choice for high-performance applications. In this article, I would like to present to you my take on why Rust.