State version.
The data properties of a state, excluding transition methods and observers, read-only at any depth: snapshots are frozen when handed out, and a holder is refused a write by the compiler rather than by an assignment that throws at run time.
The state type
State version.
The data properties of a state, excluding transition methods and observers, read-only at any depth: snapshots are frozen when handed out, and a holder is refused a write by the compiler rather than by an assignment that throws at run time.