Why doesn C++ have a universal class Object?
• We don’t need one: generic programming provides statically type safe alternatives in most cases. Other cases are handled using multiple inheritance. • There is no useful universal class: a truly universal carries no semantics of its own. • A “universal” class encourages sloppy thinking about types and interfaces and leads to excess run-time checking. • Using a universal base class implies cost: Objects must be heap-allocated to be polymorphic; that implies memory and access cost. Heap objects don’t naturally support copy semantics. Heap objects don’t support simple scoped behavior (which complicates resource management). A universal base class encourages use of dynamic_cast and other run-time checking. Yes. I have simplified the arguments; this is an FAQ, not an academic paper.
