Name

union keyword — Declares a union

Synopsis

               class-key := union

The union keyword declares an aggregate type, similar to a struct, but the union object can store only one member at a time. The storage for all members overlaps. A union can have member functions (including constructors and destructors) but not virtual member functions. A union cannot be or have a base class. Union members cannot be static or references. Data members cannot have constructors, a destructor, copy-assignment operators, virtual functions, or virtual base classes. An initializer for a union can initialize only its first member.

See class for the syntax rules.