On 7/26/2010 12:13 PM, Mark Davis ☕ wrote:
I agree that having it stated at point of use is useful - and we do
that in other cases covered by stability clauses; but we can only
state it IF we have the corresponding stability policy.
Mark,
The statement in your "but" clause really isn't correct.
Writing
"A character is given/is assigned the X property if...."
is a type of statement that is made everywhere in the definitions of
properties. For an example look no further than chapter 4 ("Pairs of
opening and closing punctuation are given their General_Category
values...").
Therefore, the principal difference between my proposed formulation to
the current text (other than details of phrasing) is the "only if" part.
The "only if" refers to the fact that "Decimal_digit" is currently not
assigned for characters used as decimal digits that are out of order.
Therefore, there's nothing in the proposed language that couldn't be
stated right now for 6.0.
If you want a stability guarantee on top of that, it's really easy to
state *after* you've clarified the definition of "decimal_digit".
"The definition of Decimal_Digit will not change".
*That* would be a proper stability guarantee.
A./
PS: I'm, like John, rather skeptical about adding a formal item to the
stability policies, but if a majority feels otherwise, I would strongly
recommend to first make a tight definition, and second, freezing that
definition, rather than repeating the definition in the stability
policies where it's hard to follow and out of context.
Proposed text:
//
"A character is given the decimal digit property, if and only
if, it is
used in a decimal place-value notation and all 10 digits are
encoded
in a single unbroken run starting with the digit of value 0, in
ascending
order of magnitude".
