Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
According to the text I am referring to (The Complete Reference by Herbert Schildt) a derived class doesn’t inherit friend functions and friend functions may not have a
storage-class specifier. That is, they may not be declared as static or extern. Why?
Because that would break encapsulation: the derived class couldn’t control its friends any longer so it effectively cannot control who has access to its internals.
Becausestaticwould make no sense (it only makes sense in functions belonging to a class, andfriends are free functions), andexternwould once again violate encapsulation because the class effectively cannot control any longer which function has access to it: due to beingextern, the friend could effectively come from a different compilation unit, unknown to the class.See Jan’s answer for a correction.