Null-coalescing operator (??)
- returns the left-hand operand if the operand is not null; otherwise it returns the right hand operand
- The result of a
??
operator is not considered to be a constant even if both its arguments are constant
Example:
// Set y to the value of x if x is NOT null; otherwise,
// if x == null, set y to -1.
int y = x ?? -1;