init DateTime is very annoying because we always need to initialize the DateTime object

[slangmgh]

When I include the `DateTime` into the object, I cannot use the object freely 
because the compiler always complain that the `DateTime` field is not 
initialized.
    
    
    type
       User = object
          name: string
          age: int
          birthday: DateTime
    
    var u = User(name: "John", age: 20)  # ERROR! field not initialized: 
birthday
    var x: User    # Warning: Cannot prove that 'x' is initialized
    

The simple workround is use Time instead, but not very convenient.

Is there any good way to solve the problem?