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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Initializing an array of tasks with discrimants
Date: Sat, 23 Nov 2019 18:03:54 +0100
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Date: 2019-11-23T18:03:54+01:00
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On 2019-11-23 17:28, Jere wrote:

> Yes, for ID's.  I really dialed down the example
> code for simplicity.  The actual scenario isn't
> ID's but a set of enumerations that provide
> configuration data for the tasks.

Then you should rather ask when Ada will get user-defined constructors 
and user-defined aggregates.

The former is required to determine task discriminants from whatever set 
of parameters ("virtual disciminants") you please.

The latter is required to initialize array using a procedure handing a 
list of whatever "virtual" elements.

> I was mostly just seeing
> if I could do away with the wrapper record for
> initialization.

And make your program unstable because of using hideous kludges no Ada 
vendor will ever make work same way in two consecutive compiler versions?

I would rather stay safe: Ada 95 + interfaces (where needed) + prefix 
notation (where needed), no fancy stuff.

Good old task initialization patterns:

1. Start entry

    task type T is
       entry Start (whatever parameters);
       ...
    end T;

    V : A (1..10);
begin
    V (1).Start (...);
    V (2).Start (...);
    ...

2. Task parameters factory object, e.g. passed as an access discriminant.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de