Re: New aggregates with Ada 2022.

[Simon Wright <simon@pushface.org>]

Blady <p.p11@orange.fr> writes:

> Le 19/06/2022 à 16:15, Simon Wright a écrit :
>> Blady <p.p11@orange.fr> writes:
>> 
>>> aarm_202x_ch04.adb:491:40: error: container aggregate must use [], not ()
>> If you look at ARM202x 4.3.5, you'll see that *container* aggregates
>> must use []. I'm sure there wa a whole lot of argument about this in the
>> ARG!
>
> Yes I was aware of that but I wanted to give Empty_Map its real value
> of the full type definition.
>
> My understanding is:
> you declare the aggregate aspect as:
>       type Map_Type is private
>         with Aggregate =>  (Empty     => Empty_Map,
>                             Add_Named => Add_To_Map);
> thus:
> MM : Map_Type;
> ...
> MM := [] -- the compiler uses Empty_Map
> MM := [1=>"toto", 4=>"titi"]; -- the compiler uses Add_To_Map
>
> now if I declare:
> Empty_Map : constant Map_Type := [];
> then it could be an recursive infinite call, could be?

I think you'd need to supply the contents - Empty_Map here is presumably
the full declaration (it is in your PR). Fixing this, the compiler is
still confused (it thinks that 'others' in [others => [others => ' ']]
isn't static - also if replaced by '1 .. 10'!!!).