Runs the task (synchronously)
- ( BOOL )run;
YES if the runnable object has run successfully, otherwise NO
Runs the task with variables (synchronously)
- ( BOOL )run: ( nullable NSDictionary< NSString *, NSString * > * )variables;
YES if the runnable object has run successfully, otherwise NO
An optional error, possibly set after the task has run
@property( atomic,
readonly,
nullable ) NSError * error;
Set when the runnable object is currently running
@property( atomic,
readonly ) BOOL running;