What is the principal purpose of generics? In what sense do generics serve a broader purpose in C++ and Ada than they do in Java and C#? Under what circumstances can a language implementation share...

What is the principal purpose of generics? In what sense do generics serve a broader purpose in C++ and Ada than they do in Java and C#? Under what circumstances can a language implementation share code among separate instances of a generic? What are container classes? What do they have to do with generics?