Re: Tally

[Brad Moore <bmoore.ada@gmail.com>]

On Wednesday, January 15, 2020 at 2:03:14 AM UTC-7, Simon Wright wrote:

> 
> and then of course
> 
>    for C in Counts.Iterate loop
>       Put_Line (Count_Maps.Key (C)'Image
>                   & " -> "
>                   & Count_Maps.Element (C)'Image);
>    end loop;

This is interesting, in AI12-0189-1/07 (Loop body as anonymous procedure), there is an example given in the AI showing how the feature could be used
to similarly iterate through a map container.

   for (C : Cursor) of My_Map.Iterate loop
      Put_Line (My_Key_Type'Image (Key (C)) & " => " &
         My_Element_Type'Image (Element (C)));
   end loop;

   -- The above is equivalent to:

   declare
      procedure P (C : Cursor) is
      begin
         Put_Line (My_Key_Type'Image (Key (c)) & " => " &
            My_Element_Type'Image (Element (C)));
      end P;
   begin
      My_Map.Iterator (P'Access);
   end;

Here is another example where new Ada 2020 machinery is used to do something, which ends up looking more complicated than doing it the gool ol' Ada 2012 way ;-). The only real difference is that "(C: Cursor)" is replacing "C", and its an "of" loop, rather than an "in" loop.

While the example is illustrative, I think a better example is needed at least, 
as we shouldn't be showing an example if it is ultimately not the recommended way to tackle the problem. I would recommend Simon's loop over this.

Brad