Why use generic constraints in C#

Question

I\'ve read an excellent article on MSDN regarding Generics in C#.

The question that popped in my head was - why should i be using generic constraints?

For ex

Answer 1

Consumer of your class gets the benefit of increased type-safety, among others.

class Widget : IPokable { }

// No generics
Widget w = (Widget)list[0]; // cast can fail

// With generics
Widget w = list[0];

Without generics, if list was containing IPokable objects, cast is still necessary.

Class you're implementing gets the benefit of using specific methods on the generic object.

class PokableList where T : IPokable {
    public T PokeAndGet() {
        currentObj.Poke();
        return currentObj;
    }
}