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From: tmoran@acm.org
Newsgroups: comp.lang.ada
Subject: Re: Variant Record Component
References: <3E5D00D6.F6A20AD2@boeing.com>
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Date: Wed, 26 Feb 2003 21:37:47 GMT
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Date: 2003-02-26T21:37:47+00:00
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> Is there a way to determine if an object of some variant record type
> contains a specific variant component, other than a trying it and
> handling a possible constraint error?
 Do you mean a situation with a non-simple "case" like:
   type r(v : integer) is record
     case v is
       when 0 => a:integer;
       when 1 | 2 | 3 => b:integer;
       when others => null;
     end case;
   end record;
where you would essentially have to replicate the "case" statement,
and you would rather just ask "if x.b exists"?