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Newsgroups: comp.lang.ada
Date: Thu, 14 Jun 2018 09:58:12 -0700 (PDT)
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Subject: Re: Unknown constraints and type composition
From: sbelmont700@gmail.com
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Xref: reader02.eternal-september.org comp.lang.ada:53103
Date: 2018-06-14T09:58:12-07:00
List-Id: <comp.lang.ada>

One approach would be to use coextensions, assuming you are aware of all that entails, e.g.:

type Inner (<>) is private;
function Create_Inner return Inner;

...

type Outer (<>) is private;
function Create_Outer return Outer;

private
type Outer (x : access Inner) is null record;

function Create_Outer return Outer is
begin
  return Outer (x => new Inner'(Create_Inner));
end Create;


And, assuming the compiler follows the advice (and is bug free :/ ) everything should work itself out safely and neatly.  Though a portable way to do this would be nice.

-sb