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From: maa@liacc.up.pt (=?ISO-8859-1?Q?M=E1rio_Amado_Alves?=)
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Subject: Re: DYNAMIC ADA TASK CREATION?
Date: 2 Jul 2003 05:05:42 -0700
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"Why not:
   type Element (<>) is limited private;" (Dmitri)

"Because the type must be definite, of course! Otherwise, how would
you know how much space to allocate for the object?" (Matthew)

With the amazing 'Size attribute, of course!

What I have *not* figured out yet is how to use the really amazing
'Definite attribute to choose the most efficient implementation
automatically (at compile or at run time).

Matthew should remember the small talk we had about this in Toulouse.
His impression was this is not possible and after a little research
that is my impression too. But never loose hope! Namely there is
always Ada 2015:

  -- Don't try this at home!
  generic
    type Element_Type (<>) is private;
  package Unbounded_Arrays is
    when Element'Definite =>
      new package Unbounded_Arrays_For_Definite_Elements
(Element_Type);
    when not =>
      new package Unbounded_Arrays_For_Nondefinite_Elements
(Element_Type);
  end;

Cheers,
--Marius