What are the best practices for using const variables in C++?

What are the best practices for using const variables in C++?

Using const variables in C++ helps to prevent accidental modification of values. Best practices include declaring constants at the top of your file, using const for function parameters when they shouldn't be modified, and using constexpr for compile-time constants.

Can you give me an example of using const in a function?

Sure! Here's an example:

void printValue(const int value) {
    std::cout << "Value: " << value << std::endl;
}

In this function, value cannot be modified inside the function.

What about using const with pointers?

When using const with pointers, you can have:

• const int* ptr: a pointer to a constant integer (the integer cannot be changed through the pointer).
• int* const ptr: a constant pointer to an integer (the pointer cannot be changed to point to another integer).
• const int* const ptr: a constant pointer to a constant integer.

Are there any performance benefits to using const?

Yes, using const can lead to performance improvements by enabling compiler optimizations. It also makes your code safer and easier to understand.