Re: Musing on defining attributes and the ability to define an "abstract type X"-interface.

["Randy Brukardt" <randy@rrsoftware.com>]

"Shark8" <onewingedshark@gmail.com> wrote in message 
news:ae46a44e-ee1e-42f6-ae8d-a02ae012e31d@googlegroups.com...
...
>IOW, what I want to do is leverage the language's underlying concepts, 
>making
>them explicit, and using *THAT* to unify/define what is already (in some 
>sense)
>required... like how universal_integer attributes require a bignum package, 
>but
>the language doesn't require its exposure.

I made a stab at this some years ago (see the discussion of AI12-0021-1); 
the idea was to define a Root_String_Type that all of the others are derived 
from. Some messing around is needed to get literals and conversions. Idea 
being that a routine taking a Root_String_Type'Class parameter could handle 
any text string, with any representation or storage management (i.e. 
unbounded or fixed), without any explicit code.

I have no idea if there is any interest in pursuing this approach, or some 
similar approach; I don't think we ever discussed it in a meeting. 
Internationalization is supposed to be further addressed in Ada 2020, so I 
would hope that we'd discuss it someday soon.

                      Randy.