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From: Jeffrey Carter <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: "NULL" returned by a function
Date: Sat, 09 Aug 2014 08:13:38 -0700
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Date: 2014-08-09T08:13:38-07:00
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On 08/09/2014 05:45 AM, Victor Porton wrote:
>
>     type String_Or_Null (Has_Value : Boolean := False) is
>        record
>           case Has_Value is
>              when False => null;
>              when True => Str: String;

    when True =>
       Value : Unbounded_String;

>           end case;
>        end record;

This assumes you need to distinguish between no string and the null string (""). 
Otherwise you can just return String.

-- 
Jeff Carter
"Insufficient laughter--that's grounds for divorce."
Play It Again, Sam
126