Rust vs. C++: Differences and use cases

C++ was mature before Rust even existed. Does that mean developers should switch from C++ to Rust? Not always.

Programmers have no shortage of choice when it comes to the language for a new project. C++ and Rust suit projects from browser-based software to video games, and each has advantages.

C++ is an efficient, reliable programming language. Developers choose C++ for its dependability, performance and scalability. Extensive library support offers functions from the C++ Standard Template Library (STL). This language is used for systems programming, video game development and modern applications that run on OSes and web browsers.

Rust is a multiparadigm, compiled programming language that developers can view as a modern version of C and C++. It is a statically and strongly typed functional language. Rust uses syntax similar to C++ and provides safety-first principles to ensure programmers write stable and extendable, asynchronous code. Developers use Rust for general programming, web development, data science and video gaming, as well as for augmented reality (AR), virtual reality (VR) and blockchain projects.

C++ came about in 1985, while Rust's first stable release was 30 years later in 2015. Despite the age difference and additional safety features found in Rust, not all C++ codebases need to migrate to Rust. Examine the qualities of C++ and Rust, their differences as well as their similarities, to choose between the two programming languages.

Why programmers use Rust

Rust's feature set emphasizes thread safety, memory layout control and concurrency. Its built-in security is a plus for modern software and systems.

Within systems languages, concurrency can be fragile and error-prone. Such weaknesses can result in information loss and integrity deficits.

Threads enable different software components to execute simultaneously. Concurrency of threads can present challenges in software. Rust ensures safe concurrency of threads, which helps microservices applications to operate as expected. The language is based on a principle of ownership in which any given value can be owned by a single variable at a time.

In Rust, compilation units are called crates. A crate is an atomic unit of code for the Rust compiler. Rust won't compile programs that attempt unsafe memory usage. Through syntax and language metaphors, the Rust compiler prevents thread- and memory-related problems such as null or dangling pointers and data races from occurring in production.

The static analysis tool in Rust's compiler, borrow checker, halts compilation before unsafe code can cause a memory error. Programmers must therefore resolve these issues early in the development process. Borrow checker analyzes how value ownership can change across a program's lifetime. Values held by one place can be borrowed by other places in a code base. Borrow checker uses this set of rules to prevent data races in concurrent code as well.

The compiler also manages ownership distribution and memory allocation among objects to avoid issues at runtime. Memory safety prevents buffer overflows and protects against a class of bugs related to memory access and use. This means, for example, that increasing the amount of Rust code within a browser-based application will decrease the attack surface for breaches and vulnerabilities.

Rust offers powerful abstractions as well. Its rustup installer sets up the development environment and cross-compiling. All the elements necessary to produce Rust binaries exist in the same package.

How to get started with Rust

Developers new to Rust can pick up the core principles of the language by learning to use the Cargo package manager, with its numerous API bindings to common libraries and frameworks. Developers commonly use IDEs such as Microsoft Visual Studio Code, JetBrains CLion and IntelliJ IDEA. Actix Web and Rocket are popular web frameworks for Rust.

Because the Cargo library doesn't rank the effectiveness of crates, developers need to experiment or poll the Rust community for input. The Rust community is inclusive and supportive. The Rust Foundation supports meaningful contributions to the ecosystem, furthers Rust outreach and promotes language adoption. It took over the language from founding company Mozilla.

Why programmers use C++

C++ originated as an extension of the C language for cross-platform programming. It offers effective functionalities, safety and ease of use. It has a three-year release cycle, with new features introduced regularly. Version C++23 is scheduled for December 2023.

C++ has more complex syntax than some other languages and a great deal of abstraction, but it offers benefits for modern development. High levels of abstraction enable developers to encapsulate hardware and OS implementation details. It's a fit for embedded systems that require code to be close to the hardware, such as IoT devices, smartwatches and medical devices.

Abstract classes express pure virtual functions. Programmers can concentrate on grouping classes to make a program's codebase organized and understandable. Abstraction also reduces program duplication and promotes reusability. Developers can also improve program privacy via abstraction in the design, ensuring that users only see pertinent data.

C++ is a compiled language with written code translated directly into machine code. This construct makes the language fast, efficient and flexible. C++ takes advantage of hardware capabilities to accelerate scalability, through low-level control. This feature suits video games, GUIs, scientific simulations and financial applications. It can handle large volumes of data, so it is effective for processing the enormous data sets necessary to produce immersive 3D AR/VR experiences.

C++ memory management allocates memory at runtime and deallocates it when it's not required. Free memory access in C++ can lead to buffer overruns and stack overflow vulnerabilities. These safety and security deficits require time and resources for debugging, a downside of C++. These concerns particularly affect domains that use embedded languages, such as automotive and medical fields and aerospace and aviation. Security guidelines for C++ yield memory safety with the language.

The relatively long life of C++ has contributed to an expansive, open source STL, a collection of frameworks and a supportive community. Developers can make their jobs easier by accessing numerous built-in functions, containers, hashmaps, heaps and related features.

Code in the STL is tested and scrutinized by community members. The community's work enables programmers to simplify their code; write cleaner, faster code; and avoid maintenance issues. The library also includes generic algorithms and specifies the syntax and semantics for these instructions. Performance requirements for these algorithms correspond to accepted standards and benchmarks.

While the C++ community is supportive and enthusiastic, no forum or group exerts centralized control. A committee meets yearly to update official documents.

Developers with preexisting code can switch from C++ to more secure languages, such as Rust. However, millions of lines of preexisting C++ code don't require new levels of safety. So, while Rust is a newer alternative, C++ is a durable option with future viability.

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