useClosureListener and useClosureFilter

[deanrad]

When an event listener (or filter) needs to always have the latest of certain React variables,
useClosureListener and useClosureFilter accept:

• A criteria
• A handler (a 'bound' function closing over some values)
• An observer (if a listener - does not apply to filters)
• A deps array - any change in one of these will replace the handler with the one given (per useEffect)

One good application for useClosureFilter is to create a component whose job is to listen to certain events, and add stuff to their payload - stuff that depends on React current values.

// Adds to the payload of FILE_OPEN events the CURRENT_USER.userId
const FILE_OPEN = createEvent('file/open');
const { data, loading } = useQuery(CURRENT_USER);
useClosureFilter(
  FILE_OPEN,
  (e) => { e.payload.userId = data?.userId; return e; }, 
  [data]
);