When Should You Use the `noexcept` Keyword in C Function Declarations?

When to Utilize noexcept for Function Declarations

Question:

When should the noexcept keyword be applied to function declarations?

Answer:

1. Functions Known Not to Throw:

If a function is guaranteed never to throw an exception, but the compiler cannot infer this on its own, consider appending noexcept to its declaration. However, adding noexcept unnecessarily may hinder productivity. Therefore, exercise caution when using noexcept for every function declaration.

2. Situations Where noexcept is Beneficial:

Use noexcept when:

• The Big Four (constructors, assignment, not destructors as they're already noexcept): This enables potential performance improvements in template code, such as std containers.
• Functions that rely on move operations: noexcept on move constructors eliminates the need for forced throws, which can result in performance benefits.

Performance Improvements with noexcept:

Question:

Can noexcept lead to performance enhancements? Provide an example.

Answer:

• Modern compilers exploit noexcept to generate more efficient machine code.
• Enabling move operations through noexcept can optimize memory management and reduce execution time.

Conclusion:

The appropriate use of noexcept remains a matter of best practices based on real-world scenarios. Nonetheless, it is a valuable tool for indicating functions that are guaranteed not to throw exceptions, potentially leading to improved performance and code optimization.

The above is the detailed content of When Should You Use the `noexcept` Keyword in C Function Declarations?. For more information, please follow other related articles on the PHP Chinese website!