public static IObservable <CollectionAddEvent <T> > OnAdd <T>(this IEnumerable <T> collection)
{
var previousCollection = new List <T>();
return(Observable.EveryUpdate().SelectMany(_ =>
{
var changedItems = collection.Where(item => !previousCollection.Contains(item)).ToList();
var index = 0;
var events = changedItems.Select(item =>
{
var evt = new CollectionAddEvent <T>(index, item);
index += 1;
return evt;
});
previousCollection = collection.ToList();
return events;
}));
}
public bool Equals(CollectionAddEvent <T> other)
{
return(Index.Equals(other.Index) && EqualityComparer <T> .Default.Equals(Value, other.Value));
}