Hands-On Design Patterns with C++

Questions

1. What is the effect of declaring a function as a friend?
2. What is the difference between granting friendship to a function versus a function template?
3. Why are binary operators usually implemented as non-member functions?
4. Why is the inserter operator always implemented as a non-member function?
5. What is the main difference between argument conversions for template and non-template functions?
6. How can we make the act of instantiating the template also generate a unique non-template, non-member function?