So I conducted a research recently and was able to put up some deeply useful tips about how to implement the Rule of three carefully in C++. Though the rule of five is taking over in exception safety, it's still good to know this stuff.

The rule of three is a mathematical rule with tech and even philosophical translations, and it's Google-defined as, "a method of finding a number in the same ratio to a given number as exists between two other given numbers."

The Rule of three is wonderfully useful for writing exception-safe codes in C++, along with the rule of five.

The rule of three states, that the copy constructor, the assignment operator and the destructor must always go together as member functions. A class that defines one must always define the other two.

Major tip I tested out: If you manage dynamically-allocated resources with smart pointers, you won’t actually need a custom destructor. The smart-pointer object will take care of deletion for you. You really only need a custom copy-constructor and a custom copy-assignment operator.

The rule of three is getting out of date with the rule of five, but I thought the tip might be good to share, for C++ers.

The rule of three is wonderful when you want to modify an object data, so you append updates of the copy constructor and assignment operator temporarily.

How can I get in touch with you??

C++ my first love. One has to be careful with pointers though. Improper use could have serious implications for you programs. First I am hearing of Rule of Three and Rule of Five. Thumbs up for the info.

computergeek:

Major tip I tested out: If you manage dynamically-allocated resources with smart pointers, you won’t actually need a custom destructor. The smart-pointer object will take care of deletion for you. You really only need a custom copy-constructor and a custom copy-assignment operator.

That had been known way before C++11 smart pointers (unique_ptr, shared_ptr ...). That's the point of RAII.

The rule of three states, that the copy constructor, the assignment operator and the destructor must always go together as member functions. A class that defines one must always define the other two.

Destructor is only needed
- for cleanups: when you dynamically allocate, freeing external resources etc.
- or when u need destruction to be done in a certain way.
Otherwise it's pretty useless defining a dtor.