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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: Ada Successor Language
Date: Fri, 29 Jun 2018 15:35:42 -0500
Organization: JSA Research & Innovation
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Xref: reader02.eternal-september.org comp.lang.ada:53447
Date: 2018-06-29T15:35:42-05:00
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"Niklas Holsti" <niklas.holsti@tidorum.invalid> wrote in message 
news:fpcb15Fk3saU1@mid.individual.net...
...
> (In fact, it seems to me that Ada could allow untagged record extensions 
> as well; the effect would be the same as for tagged ones, but no 'Class 
> would be formed, and no class-wide programming or dynamic dispatch could 
> be used, so all such types would be static. It would be semantically 
> equivalent to aggregation of a component of the parent type with the 
> extension components, but would allow direct access to the inherited 
> components from the parent type. This could be a useful separation of 
> extensions from tags.)

Very early versions of Ada 9X included type extension on all composite 
types. I believe 'Class was allowed on all types. Eventually, that and many 
other things were dropped because the reviewers thought that the language 
design was too ambitious. Some of those other things have been resurfacing 
in later Ada versions - even now (Ada 2020 is adding aggregate iterators, an 
idea that was proposed and dropped from Ada 9X).

We haven't had any serious requests for reintroducing either type extension 
on untagged types nor 'Class on all types (random discussion here doesn't 
count - one needs real programming problems for a formal request).

                                          Randy.