static void Main(string[] args)
{
var myDB = new Database();
Optional <User> result = myDB.GetUser("John");
if (result.IsPresent())
{
Console.WriteLine("Found John!");
}
else
{
Console.WriteLine("Oh no we didn't find him! Let us do something else!");
}
result = myDB.GetUser("Jim");
result.IfPresent(
x => Console.WriteLine("Found him! Feel free to return things here too!")
);
var theObject = myDB.GetUser("James").OrElse(new User("Sophie"));
Console.WriteLine(theObject.Name);
Optionals.Of(new User("blah"));
}
static void Main(string[] args)
{
Optional <int> emptyOpt = Optionals.Empty <int>();
int result = emptyOpt.IfPresent(
x => {
return(x + 1);
}
);
assert(result == default(int));
Optional <int> fullOpt = Optional <int> .Of(32);
result = fullOpt.IfPresent(x => { return(x + 1); });
assert(result == 33);
}
public Optional <User> GetUser(String name)
{
User user = db.Find(x => x.Name == name);
return(user == null?Optionals.Empty <User>() : Optionals.Of(user));
}
