Re: Arrays in Ada 2012

[Simon Wright <simon@pushface.org>]

"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:

> On 06/06/2017 13:47, Anatoly Chernyshev wrote:
>
>> Consider the following nice Ada 2012 construct:
>>
>> --
>> procedure test is
>>     type a1 is array(1..35,1..35,1..35,1..35,1..35,1..35) of long_long_integer;
>>     ab:a1;
>>     cnt:long_long_integer:=0;
>> begin
>>    for e of ab loop
>>        cnt:=cnt+1;
>>        e:=cnt;
>>     end loop;
>> end test;
>> --
>>
>> Is there a way (e.g. some attribute) to find the indices of the
>> array  for a current e within the cycle above?
>
> The greater dimension index changes first, so:

I don't think this is right? it's the last index that changes first,

   with Ada.Text_IO; use Ada.Text_IO;
   procedure Arrays is
      type A1 is array (0 .. 1, 41 .. 42) of Integer;
      A : A1 := ((1, 2), (3, 4));
   begin
      for E of A loop
         Put (E'Img);
      end loop;
      New_Line;
      for J in A'Range (1) loop
         for K in A'Range (2) loop
            Put_Line (J'Img & K'Img & A (J, K)'Img);
         end loop;
      end loop;
   end Arrays;

produces

$ ./arrays
 1 2 3 4
 0 41 1
 0 42 2
 1 41 3
 1 42 4
 
> I6 := Count mod 35 + 1;
> I5 := (Count / 35) mod 35 + 1;
> I4 := (Count / 35**2) mod 35 + 1;
> I3 := (Count / 35**3) mod 35 + 1;
> I2 := (Count / 35**4) mod 35 + 1;
> I1 := Count / 35**5 + 1;

Should be able to use 'Length (N) in there!
ARM 3.6.2(10),
http://www.ada-auth.org/standards/rm12_w_tc1/html/RM-3-6-2.html#p10