Re: What is the difference of "with null record" and "with private"?

["Dan'l Miller" <optikos@verizon.net>]

On Friday, May 23, 2014 1:19:16 PM UTC-5, Victor Porton wrote:
> What is the difference of "with null record" and "with private"?
> 
> 
> 
> Both denote a descendant of a type with no new additional public fields.

You will see the answer when you focus on why you yourself wrote the word "public" there.  I suspect that even you would suspect the falsehood of:  Both denote a descendant of a type with no additional fields.

> What is the difference and when one or another should be used?

  When the public view of a record is declared 'with null record', then that record has no additional fields--neither public nor private/encapsulated.  When the public view of the record is declared "with private" the record may optionally have additional private/encapsulated fields that are maintained safely by subprograms in that package.

> I see no difference.

That is because you are wearing the blinders of "public".  Look from the bigger picture of the 'private' vantage point to see what more can go on behind the curtain.