The scope
Cmdr applications can be modal. An application can accept different commands in diferent modes. The mode the application is in is determined by the scope
it is in. Each scope has commands defined on it that are available to the user when that scope
is active.
The getting started example had the GreeterScope
as its single scope. But multiple scopes can be defined. Any type annotated with the #[cmdr]
macro can act as a scope. The scope can hold state that can be accessed by the commands.