C++ pass by const pointer or by reference to const pointer


Taoist group

I'm learning c++ and recently I read a book that recommends that you use references to const when possible (if the underlying object doesn't change).

I have a question, you should pass a reference to a const pointer instead of a const pointer if possible, because references prevent copying. If not, when should I use a reference to a const pointer.

E.g:

Node(..., Node *const next = nullptr);

or

Node(..., Node* const& next = nullptr);
helmet display

Passing by const reference is a good practice when passing by value (resulting in parameter copying) is a heavy operation.

For example, when you pass a class with some properties to a function, it's better to pass it by const reference; on the other hand, if you're passing a type like intor just a pointer , it's better not to use a reference, because then Will cause performance degradation due to de reference process.

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C++ pass by const pointer or by reference to const pointer

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Taoist group I'm learning c++ and recently I read a book that recommends that you use references to const when possible (if the underlying object doesn't change). I have a question, you should pass a reference to a const pointer instead of a const pointer if p

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