Re: Prime sieve

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

On 05/27/2015 07:35 AM, montgrimpulo wrote:
> with Ada.Text_IO;         use Ada.Text_IO;
> with Ada.Integer_Text_IO; use Ada.Integer_Text_IO;
> procedure Primes_by_Sieve is
>    task type Sieve is
>       entry Pass_on (Int : Integer);

What happens when someone passes a negative value to Pass_On? If only a certain
range of values is acceptable, it's better to use an appropriate (sub)type to
prevent the use of invalid values.

>    type Sieve_Ptr is access Sieve;

Access types are not needed for this problem. Not using this access type
simplifies the body of Sieve.

>    task body P6n is
>       Limit : constant Integer := 2580976;

This constant does not need to be typed. I always prefer named numbers to typed
constants.

The ARM only guarantees a range of -(2 ** 15) + 1 .. (2 ** 15) - 1 for Integer.
This value makes your program non-portable.

>       while Num <= Limit loop

Why not use a for loop?

-- 
Jeff Carter
"This school was here before you came,
and it'll be here before you go."
Horse Feathers
48