static void Main(string[] args)
{
var provider = new InMemoryCacheProvider();
var r = new CachedRepository(provider);
r.Add(new Customer(1, "Joe", "Vella"));
r.Add(new Customer(2, "George", "Vella"));
r.Add(new Customer(3, "Tatiana", "Camenzuli"));
var id = GetCustomerId(r, "Joe");
var id2 = GetCustomerId(r, "George");
var id3 = GetCustomerId(r, new List<string>() { "George" });
var id4 = GetCustomerId(r, new[] { "Joe" });
//var allSalesByJoe1 = query1.Where(x => x.Name == "Joe").ToList();
//var allSalesByJoe2 = query1.Where(x => x.Name == "George").ToList();
//var filter1 = query1.Where(x => x.Value.Contains("t")).Select(x => x.Value);
//var filter2 = query1.Where(x => x.Value.Contains("t")).Select(x => x.Value);
//var result1 = filter1.ToList();
//var result2 = filter2.ToList();
//var t = filter1.FirstOrDefault();
}