The concept Key is a unique identifier for something in some sort of table. In general, they can be only created by the table and are returned when a appropriate new_foo() method is called on the table. There are two classes of values for a Key, valid and invalid. The latter cannot refer to something in a table. Use the method is_valid() to differentiate.

Key a;
The default constructor is guaranteed to construct an invalid key (i.e. one which is false when cast to a bool.


bool a.is_valid () This method returns false if the key was created using the default constructor or was otherwise created to be invalid.

std::ostream& std::ostream& << Event
Write a text description of the key to a standard stream.

Has Models

Kinetic::Simulator::Event_key, Kinetic::Active_objects_vector<Object>::Key.