Argentum classes and interfaces can be parameterized:

class UnorderedMap(Key, Value) { ... }
interface InStream(T) { ... }

These parameters can be used in inheritance, field and method declarations as well as inside methods.

class Map(K, V) {
   +Array(Pair(K, V));            // Base class parameterized with our class parameters
   getAt(key K) ?V { ... }        // Class parameters affect types of method prototypes
   setAt(key K, newVal V) { ... }
   forEach(visitor (K, V)void) { ... } // visitor lambda is typed with class parameters.
   ...
}
class Pair(A, B) {
  a = ?A;  // field `a` of type `Optional(A)` initialized with `none`
  b = ?B;  // Field types also depend on class parameters.
}

Right now the internal implementation of generics is does not allow instantiation-of and casts-to the parameters, but I can easily add them to the language in the future.

So bottom line is:

• Now it become very easy to implement a rich container and standard algorithms library right in the Argentum language without using C/C++.
• Switching to generics allowed to remove all type-casts from all examples, tests and tutorials. It dramatically simplified source code.

These generics do not introduce additional code, do not consume memory and do not cost CPU time.