Re: Calling inherited primitive operations in Ada

["amo...@unizar.es" <amosteo@unizar.es>]

On Thursday, September 1, 2022 at 11:33:47 PM UTC+2, Jeffrey R.Carter wrote:
> On 2022-09-01 20:54, Emmanuel Briot wrote: 

> As presented, this seems very over complicated. Elements and Definite_Elements 
> add no value, and this is just a complex way of writing 

Going in a tangent, and I guess you know perfectly well, but this is caused by the painful duplication of code that Ada pushes you to by not having a native way to abstract storage of definite vs indefinite types. So the provider of a generic library very soon faces this conundrum about duplicating most interfaces, if not implementations, or resort to non-trivial generics, or accept an unnecessary penalty for definite types, or push to the client the definite storage matter. There's simply no satisfying solution here [that I know of]. The duplication of every standard container to have both [in]definite variants is a strong indictment. 

I can understand the desire to have full control of allocation and object sizes, but that there's not a language way to work around this duplication, with appropriate restrictions to go with it, is... bothersome. Not making a dig at the ARG, which I understand is overstretched as it is. 

There was a proposal circulating some time ago that seemed promising, that I can't quickly find. Something like

type Blah is record
    Dont_care_if_in_heap: new Whatever_Definiteness; -- Would apply to indefinite types or formals
end record;

I don't think it made into https://github.com/AdaCore/ada-spark-rfcs/ or https://github.com/Ada-Rapporteur-Group/User-Community-Input/issues or I can't find it.