Re: How to Iterate over all elements of a hashed_map.

[joakimds@kth.se]

Den tisdag 29 oktober 2019 kl. 15:20:43 UTC+1 skrev Alain De Vos:
> I found code which takes a different approach, here there is a function .Iterate public ... ,
> 
> with Ada.Containers.Indefinite_Hashed_Maps;
> with Ada.Strings.Hash;
> 
> with Ada.Text_IO; use Ada.Text_IO;
> 
> procedure Show_Hashed_Map is
> 
>    package Integer_Hashed_Maps is new
>      Ada.Containers.Indefinite_Hashed_Maps
>        (Key_Type        => String,
>         Element_Type    => Integer,
>         Hash            => Ada.Strings.Hash,
>         Equivalent_Keys => "=");
> 
>    use Integer_Hashed_Maps;
> 
>    M : Map;
>    --  Same as:  M : Integer_Hashed_Maps.Map;
> begin
>    M.Include ("Alice", 24);
>    M.Include ("John",  40);
>    M.Include ("Bob",   28);
> 
>    if M.Contains ("Alice") then
>       Put_Line ("Alice's age is "
>                 & Integer'Image (M ("Alice")));
>    end if;
> 
>    --  Update Alice's age
>    --  Key must already exist in M.
>    --  Otherwise an exception is raised.
>    M ("Alice") := 25;
> 
>    New_Line; Put_Line ("Name & Age:");
>    for C in M.Iterate loop
>       Put_Line (Key (C) & ": " & Integer'Image (M (C)));
>    end loop;
> 
> end Show_Hashed_Map;

I confirm that when you want to iterate over a hashed map and want both key and value you need to use the .Iterate function as you do in the example.

Best regards,
Joakim