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Newsgroups: comp.lang.ada
Date: Sat, 26 May 2018 16:42:21 -0700 (PDT)
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Subject: Re: Strings with discriminated records
From: Shark8 <onewingedshark@gmail.com>
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Xref: reader02.eternal-september.org comp.lang.ada:52709
Date: 2018-05-26T16:42:21-07:00
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You can do this:

Type Message(Length : Positive) is record
  Text  :  String(1..Length);
  -- Other components.
end record;