The concrete type which contains the system closure provided by the user. This struct should
not be instantiated directly, and instead should be created using
Structure describing the resource and component access conditions of the system.
The core builder of
This trait is for providing abstraction across tuples of queries for populating the type information in the system closure. This trait also provides access to the underlying query information.
Supertrait used for defining systems. All wrapper objects for systems implement this trait.