Re: Non-standard functions in GNAT's Ada.Containers packages?

["Björn Lundin" <bnl@nowhere.com>]

On 2022-09-16 17:00, Marius Amado-Alves wrote:
>>>> "for X of M loop ... end loop".
>>>
>>> Not possible for maps.
>> but you can as
>>> https://programming-idioms.org/idiom/13/iterate-over-map-keys-and-value/1511/ada>
>>
>> with Ada.Containers.Indefinite_Hashed_Maps;
>> with Ada.Strings.Hash;
>> use Ada.Containers;
>> for C in My_Map.Iterate loop
>> Put_Line ("Key = " & Key (C) & ", Value = " & Element (C));
>> end loop;
> 
> Thanks, but this is "in", not "of", requires cursors, and DOES NOT COMPILE, as probably needs like ten lines of boiler plate not show.

well, yes . I thought the for looping stuff was the important part, 
since you done want to call Next.

in or of - does it really matter here?

   for C in My_Map.Iterate loop
or
   for C of My_Map loop
is not that hurtful to my eyes.

   for K,V in My_Map.Iterate loop
or
   for K,V of My_Map loop

getting Key and Value as a tuple would be nicer of course


Anyway, I forgot to instantiate the map. Here's a compileable variant



It outputs
Key = AA, Value =  1
Key = AB, Value =  5

----------------

with Ada.Containers.Hashed_Maps;
with Ada.Strings.Hash;
use Ada.Containers;
with Text_Io ; use Text_IO;

procedure Ite is

   subtype Test_Type is String(1..2);

   package Test_Map_Pkg is new Ada.Containers.Hashed_Maps
     (Test_Type,
      Integer,
      Ada.Strings.Hash,
      "=",
      "=");

   My_Map : Test_Map_Pkg.Map;
   use Test_Map_Pkg;
begin
   My_Map.Insert("AA",1);
   My_Map.Insert("AB",5);

   for C in My_Map.Iterate loop
     Put_Line ("Key = " & Key (C) & ", Value = " & Element (C)'Img);
   end loop;

end Ite;



-- 
/Björn