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

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

Using const pointers in C++ helps ensure that the data being pointed to cannot be modified. Here are some best practices:

1. Use const with pointers to protect data.
2. Prefer const T* for pointers to constant data.
3. Use T* const for constant pointers to mutable data.
4. Always initialize pointers to avoid dangling references.

Can you give an example of a const pointer?

Sure! Here's an example:

int value = 10;
int* const ptr = &value; // ptr is a constant pointer to an int
*ptr = 20; // This is allowed, value is now 20
ptr = nullptr; // This will cause a compilation error

What about const references? How do they differ?

Const references in C++ allow you to refer to an object without copying it, while ensuring that the object cannot be modified. Unlike const pointers, const references do not require dereferencing and can bind to temporary objects.

Are there any performance benefits to using const pointers?

Yes, using const pointers can improve performance by avoiding unnecessary copies of data. It also allows the compiler to optimize code better since it knows the data won't change.