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Newsgroups: comp.lang.ada
Date: Mon, 6 Jul 2015 10:30:47 -0700 (PDT)
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Subject: Re: Declaring constants for a abstract tagged type and concrete sub
 classes
From: gautier_niouzes@hotmail.com
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Xref: news.eternal-september.org comp.lang.ada:26650
Date: 2015-07-06T10:30:47-07:00
List-Id: <comp.lang.ada>

Not sure if it is useful for you, but sometimes I define a "pre-root" type which is concrete from which I define a root type which is abstract.

http://excel-writer.sf.net/ew_html/excel_out__ads.htm#462_8

In the example, the "official" root type is actually:

  type Excel_Out_Stream is abstract new Excel_Out_Pre_Root_Type with null record;

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