Re: Ichbiah 2022 compiler mode

On 2024-09-14 08:13, Randy Brukardt wrote:

I think the parallel block is more useful for general tasking. The advantage
of using parallel structures is that they look very similar to sequential
structures, and one lets the system do the scheduling (rather than trying to
figure out an organization manually).

Tasking is not about scheduling. It is about program logic expressed in a sequential form. It is about software decomposition. Parallel constructs simply do not do that.

One of the advantages of the model I'm thinking about is that it separates
concerns such as parallel execution, mutual exclusion, inheritance,
organization (privacy, type grouping), and so on into separate (mostly)
non-overlapping constructs.

To me it is exactly *one* construct: inheritance. You should be able to inherit from an abstract protected interface at any point of type hierarchy in order to add mutual exclusion:
    type Protected_Integer is new Integer and Protected;

Ada started this process by having tagged types
a separate construct from packages;

I see modules and types as unrelated things.
  you need both to get traditional OOP,

but you can also construct many structures that are quite hard in
traditional "one construct" OOP. I think that ought to be done for all
constructs, and thus the special task and protected constructs ought to go.

Constructs yes, they must go. It must be all inheritance. The concepts must stay.

We already know that protected types cause problems with privacy of
implementation and with inheritance. Tasks have similar issues (admittedly
less encountered), so splitting them into a set of constructs would fit the
model.

The problems are of syntactic nature, IMO.
There is an issue with an incomplete inheritance model. You need not just complete overriding but also more fine mechanisms like extension in order to deal with entry point implementations. The same problem is with constructors and destructors, BTW. What should really go is Ada.Finalization mess replaced by a sane user construction hooks model for all types, class-wide ones included.
--
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de