load method
Returns a Future that completes when the next batch of requests completes.
Implementation
Future<Data> load(Id id) {
if (cache && _cache.containsKey(id)) {
return Future<Data>.value(_cache[id]);
} else {
var item = _QueueItem<Id, Data>(id);
_queue.add(item);
if (!_started) {
_started = true;
scheduleMicrotask(_onTick);
}
return item.completer.future;
}
}