C++ Best Practices

⏱ Estimated reading time: 2 min

Following best practices helps write safe, efficient, readable, and maintainable C++ code.

1. Use Modern C++ (C++11 and Later)

Prefer modern features over old C-style code.

✔ Use:

• auto

• nullptr

• Range-based for

• Smart pointers

• constexpr

❌ Avoid:

• Raw pointers (when possible)

• NULL

• C-style casts

2. Prefer RAII

Resource Acquisition Is Initialization ensures resources are released automatically.

{
    std::lock_guard lock(m);
} // mutex released automatically

3. Use Smart Pointers Correctly

• Use unique_ptr by default

• Use shared_ptr only when ownership is shared

• Use weak_ptr to avoid circular references

4. Avoid Raw new and delete

Prefer:

auto ptr = std::make_unique<int>(10);

5. Pass by Reference

Avoid unnecessary copies.

void process(const std::vector<int>& v);

6. Use const Everywhere Possible

Improves safety and readability.

void print(const int x);

7. Prefer STL Over Manual Code

• Use vector instead of arrays

• Use STL algorithms (sort, find)

• Avoid reinventing the wheel

8. Write Clear and Consistent Code

• Use meaningful variable names

• Follow consistent formatting

• Avoid overly complex logic

9. Handle Errors Properly

• Use exceptions for exceptional cases

• Avoid returning error codes unnecessarily

throw std::runtime_error("Error occurred");

10. Optimize Only When Necessary

• Profile before optimizing

• Avoid premature optimization

11. Avoid Global Variables

• Use local scope

• Prefer dependency injection

12. Use constexpr and inline

For compile-time optimization.

constexpr int size = 100;

13. Follow the Rule of Zero / Five

• Rule of Zero: Prefer classes that manage no resources

• Rule of Five: If managing resources, implement:

  • Destructor

  • Copy constructor

  • Copy assignment

  • Move constructor

  • Move assignment

14. Write Thread-Safe Code

• Protect shared data with mutexes

• Use atomic variables

• Avoid data races

15. Enable Compiler Warnings

Compile with:

-Wall -Wextra -Werror

Best Practices Summary

• Use modern C++ features

• Prefer safety over cleverness

• Write readable code

• Rely on STL and RAII

• Test and profile regularly

Conclusion

Adhering to C++ best practices leads to robust, efficient, and maintainable software suitable for real-world applications.