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));
}