What are the differences between SFINAE and Concepts in C++20?

What are the differences between SFINAE and Concepts in C++20?

SFINAE stands for Substitution Failure Is Not An Error, which allows template specialization to fail gracefully. Concepts, on the other hand, provide a way to specify constraints on template parameters more explicitly.

Can you give an example of SFINAE in action?

Sure! Here's a simple example: you can use SFINAE to enable a function only if a type has a specific member function. If the type doesn't have that member, the substitution fails, but it doesn't cause a compilation error.

How do Concepts improve code readability?

Concepts improve readability by allowing you to express the requirements of template parameters directly in the function signature, making it clear what types are acceptable.

Are there any performance differences between using SFINAE and Concepts?

Generally, Concepts can lead to better compile-time performance because they provide clearer constraints, allowing the compiler to optimize better compared to SFINAE, which can sometimes lead to more complex template instantiations.