Is there any difference if we define friend function inside or outside of class

Question

What is the difference between defining friend function inside the class or declaring inside and define outside of the class. Also why it is possible to place definition ins

Answer 1

A function can be defined in a friend declaration of a class if and only if the class is a non-local class , the function name is unqualified, and the function has namespace scope. Such a function is implicitly inline. A friend function defined in a class is in the (lexical) scope of the class in which it is defined. A friend function defined outside the class is not .

C++11, [class.friend], ¶6-7