null / Reference
String content = "It is a beautiful day."; String[] results; // Declare empty String array results = match(content, "orange"); // The match statement above will fail to find // the word "orange" in the String 'content', so // it will return a null value to 'results'. if (results == null) { println("Value of 'results' is null."); // This line is printed } else { println("Value of 'results' is not null!"); // This line is not printed }