/// <summary>
/// A simple example of how to combine expressions (i.e., how to have one expression call another).
/// </summary>
static void TestExpressionCombiner()
{
var criteria1 = Linq.Predicate <Purchase>(p => p.Price > 1000);
var criteria2 = Linq.Predicate <Purchase>(p => criteria1.Invoke(p) || p.Description.Contains("a"));
//Expression<Func<Purchase, bool>> criteria1 = p => p.Price > 1000;
//Expression<Func<Purchase, bool>> criteria2 = p => criteria1.Invoke(p) || p.Description.Contains("a");
Console.WriteLine("Here's what criteria2 looks like, before calling Expand");
Console.WriteLine(criteria2.ToString());
Console.WriteLine();
Console.WriteLine("Here's what criteria2 looks like, after calling Expand");
Console.WriteLine(criteria2.Expand().ToString());
var data = new DemoData();
// We can use criteria2 in either of two ways: either call Expand on the expression before using it:
var query = data.Purchases.Where(criteria2.Expand());
Console.WriteLine("Count: " + query.Count());
// or call AsExpandable() on the Table:
query = data.Purchases.AsExpandable().Where(criteria2);
Console.WriteLine("Count: " + query.Count());
}
