Rust Interview Questions

Rust and C++ are both systems programming languages that offer low-level memory control and high performance. However, they have significant differences in design philosophy, safety features, and ease of use. Here are the main differences between Rust and C++:

Memory Safety and Management

1. Ownership and Borrowing (Rust):

   • Rust: Enforces strict ownership, borrowing, and lifetimes rules to manage memory safety at compile time without a garbage collector.
   • C++: Relies on manual memory management, smart pointers, and the programmer's discipline to avoid memory leaks and dangling pointers.

2. Memory Safety:

   • Rust: Provides strong guarantees of memory safety, preventing null pointer dereferencing, dangling pointers, and data races at compile time.
   • C++: Allows greater flexibility but places more responsibility on the programmer, leading to potential safety issues if not handled correctly.

Error Handling

3. Error Handling:
   • Rust: Uses the Result and Option types for error handling, encouraging explicit handling of errors and absence of values.
   • C++: Uses exceptions for error handling, which can be ignored or mishandled, leading to potential runtime errors.

Concurrency

4. Concurrency:
   • Rust: Concurrency is safe by default due to the ownership and borrowing system, which prevents data races at compile time.
   • C++: Offers various concurrency mechanisms, but ensuring thread safety is the programmer's responsibility, making it more prone to data races and synchronization issues.

Language Features

5. Type System:

   • Rust: Has a strong, static type system with type inference, making code both safe and concise.
   • C++: Also has a strong, static type system but with more complexity and less type inference compared to Rust.

6. Macros:

   • Rust: Provides hygienic macros that prevent common pitfalls associated with macro use.
   • C++: Uses preprocessor macros that can lead to issues like name collisions and unexpected behavior.

Compilation and Tooling

7. Compilation:

   • Rust: Focuses on catching errors at compile time, resulting in safer and more predictable runtime behavior.
   • C++: Allows for more runtime flexibility but can result in harder-to-debug runtime errors.

8. Tooling:

   • Rust: Comes with a built-in package manager and build system (Cargo), which simplifies dependency management and project building.
   • C++: Relies on various external tools for package management and building, leading to a more fragmented tooling ecosystem.

Ecosystem and Community

9. Ecosystem:
   • Rust: Has a growing ecosystem with a focus on safety and modern development practices.
   • C++: Has a vast and mature ecosystem with a large number of libraries and frameworks, but also inherits a lot of legacy complexity.

Learning Curve

10. Learning Curve:
    • Rust: Steep learning curve due to the ownership and borrowing system, but provides extensive documentation and strong community support.
    • C++: Also has a steep learning curve due to its complexity and the need to manage memory and other resources manually.

Performance

11. Performance:
    • Rust: Aims to provide performance comparable to C++ with safer abstractions.
    • C++: Known for high performance and fine-grained control over hardware, often used in performance-critical applications.

Summary

In summary, Rust and C++ both offer powerful capabilities for systems programming, but they take different approaches to safety, memory management, concurrency, and tooling. Rust emphasizes safety and modern language features, making it a compelling choice for new projects focused on reliability and maintainability. C++ offers unparalleled performance and flexibility, with a vast ecosystem and a long history of usage in various domains. The choice between Rust and C++ will depend on the specific requirements of the project, the team's familiarity with the languages, and the priority given to safety versus flexibility.