Ada 83 did not provide enough control on the creation, assignment, and destruction of objects of user-defined types. This lack of control restricted type composition and prevented the full exercise of information hiding on Abstract Data Types. Ada 9X brings new mechanisms supporting the full control of Abstract Data Types, powerful type composition, and more extensive information hiding. With better control of Abstract Data Types, Ada code will be easier to write, understand, and reuse. Thus, applications written in Ada 9X will be safer.
Keywords: Abstract data types, Information hiding, Ada 9X, Object initialization, User-defined Assignment, Object finalization, Memory Reclamation, Reference counting, Type composition.