C# generation: from '?' via '??' to '???'

C# include several usable but not famous operators. Today we'll consider the generation of  operator '?'.
The first and known from language C old operator '?' was appeared in C# 1.0 in the Visual Studio 2002. An operator using for condition instead to block  if-else:

1. Random rnd = new Random();
2. //Long way
3. bool isLessTo50;
4. if (rnd.Next(100) < 50)
5. {
6.    isLessTo50 = true;
7. }
8. else
9. {
10.    isLessTo50 = false;
11. }
12.  
13. //Short way
14. bool isLessTo50 = rnd.Next(100) < 50 ? true : false;

The next '??' was offered 3 years later in Visual Studio 2005. The ?? operator is called the null-coalescing operator. It returns the left-hand operand if the operand is not null; otherwise it returns the right hand operand:

1. DateTime? dt = GetDate();
2. //Regular way
3. if (dt != null)
4. {
5.    return dt;
6. }
7. else
8. {
9.    return DateTime.Now;
10. }
11. 
    
12. //Short way
13. return (dt != null) ? dt : DateTime.Now;
14. 
    
15. //New way
16. return dt ?? DateTime.Now;

The last operator '???' was announced in Visual Studio 2012. I'm very like it because he is cutting the validation of object:

1. class Person
2. {
3.  public string Name { get; set; }
4.  public int ID { get; set; }
5. }
6.  
7. //The program
8.  Person person = InitPerson();
9. 
   
10. //Old way
11. if (person != null)
12. {
13.   return person.ID;
14. }
15. else
16. {
17.   return default(int);
18. }
19.  
20. //New way
21. return person.ID ??? default(int);

In Visual Studio 2014 the operator '?..' did not receive renewal but maybe in next versions we'll see '????'  and even '?????' :-).

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