Clause 23: Ning to Non-member, Non-friend, replace the member function.

Consider the following frequently occurring use patterns:

class webbroswer{public    : ...     void ClearCache ();     void clearhistory ();     void removecookies ();    ...};

Then it would be natural to think of adding such a clean-up method:

class webbrowser{public    : ...     void cleareverything ();};

Or a way of cleaning up:

void clearbrowser (WebBrowser & WB) {    wb.clearcache ();    Wb.clearhistory ();    Wb.clearcookie ();}

If you want to choose between a member function with the same functionality and a non-member, Non-friend function, then a high encapsulation is non-member, non-friend function. (Pay attention to the encapsulation here, let a function become a class of non-member), does not affect its become another class member function, such as the above Clearbrowser function, it can be completely as a tool class static member function) It is generally good practice to have clearbrowser placed in the same namespace as Clss WebBrowser. Like this:

namespace webbrowserstuff{    class  webbrowser{...    }; void clearbrowser (WebBrowser & WB); // convenience functions such as clearbrowser can declare multiple in a namespace. };

And because namespace can exist across header files, it is also convenient for such tool functions to maintain cross-header files. Summary: Remember that you should replace the member function with the Non-member non-friend function, which can increase encapsulation, wrap elasticity, and function expansion properties.

Clause 23: Ning to Non-member, Non-friend, replace the member function.