Re: Subtypes boundaries

["Jeffrey R. Carter" <spam.jrcarter.not@spam.acm.org>]

Nobody wrote:
> 
> I am new to Ada and found the following declaration in my text book:
> 
> type ASTERIX is range -5_000..+10_000;
> subtype IDEFIX is range 1..20_000;

Which text book are you using? All caps for identifiers has not been commonly 
used for 15 years or more.

If you really found that in your text, you should get another text. The 
declaration of Idefix is invalid, as it does not give the parent subtype. A 
valid subtype declaration is

subtype Positive is Integer range 1 .. Integer'Last;

You are correct that the range of a subtype cannot exceed that of its parent.

-- 
Jeff Carter
"Apart from the sanitation, the medicine, education, wine,
public order, irrigation, roads, the fresh water system,
and public health, what have the Romans ever done for us?"
Monty Python's Life of Brian
80