Observing Resources

Something that can observe changes to the state of a Resource. “State” means latestData, latestError, and isLoading.

Any code that wants to display or process a resource’s content should register itself as an observer using Resource.addObserver(...).

A closure alternative to ResourceObserver.

See Resource.addObserver(owner:file:line:closure:).

The possible causes of a call to ResourceObserver.resourceChanged(_:event:).