Photuris // Variable-Precision numbers

[rivest@theory.lcs.mit.edu (Ron Rivest)]

I wrote in a previous note:
> Page 11: Section 2.5 Variable Precision Numbers
>
> 	It seems possible that a variable-precision number could have
>  	a size of 0 octets.  Indeed, many of the examples given have
> 	exactly that (e.g. the Validity-Choice field on pages 27--28 are
>         shown as 16-bits, which must be a size of 0).  Yet the value
>         of such a quantity is undefined.  Is it 0?
>
To which Bill Simpson replied:
>Yes.  Fixed:
>
>   A value of zero is represented by a Size of zero, and no value field.
>
>   A value of one is represented by a Size of one, and no value field.
and now I'm confused.

Representing a value of one by a Size of one, and no value field, is 
inconsistent with the purpose of the Size field, and rules out the 
possibility of having a Size field of one with a real value field of length
one. (I am interpreting the Size field to mean the length of the Value
field only; the 2 bytes of the Size field are not counted.)

What you want is something like (bytes given in hex):

	Size	Value		Represents (decimal)
	00			0
	01	00		0
	01	01		1
	01	02		2
	...
	01	FF		255
	02	00 00		0
	02	00 01		1
	...
	02	FF FF		65535
	and so on.

Correct?

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