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Newsgroups: comp.lang.ada
Date: Sun, 12 May 2013 07:13:13 -0700 (PDT)
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Subject: Re: User defined type conversion
From: AdaMagica <christ-usch.grein@t-online.de>
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Xref: news.eternal-september.org comp.lang.ada:15527
Date: 2013-05-12T07:13:13-07:00
List-Id: <comp.lang.ada>

On Sunday, May 12, 2013 9:04:36 AM UTC+2, ldries46 wrote:
> Is a variant record perhaps the solution for your problem.
>
> type Rec = (bit16, bit 8);
>
> type ABC is
>    record
>       Option : Rec;
>       case Option
>          when bit16 =>
>               A16 : Unsigned_16;

That doesn't compile. Option must be a discriminant and then you can't change the view by just changing the discriminant.
You might think that Unchecked_Union is the solution, but the program is erroneous if the record is read with the wrong discriminant.

The correct way is Unchecked_Conversion, as has been said before.