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From: "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: Storage_Error: mine's or gnat's fault?
Date: Fri, 3 Jun 2016 15:48:03 -0700
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Date: 2016-06-03T15:48:03-07:00
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On 06/03/2016 03:45 PM, Jeffrey R. Carter wrote:
> On 06/03/2016 02:43 PM, Alejandro R. Mosteo wrote:
>>
>>    function First_Element (Container : List) return Element_Type is
>>    begin
>>       if Checks and then Container.First = null then
>>          raise Constraint_Error with "list is empty";
>>       end if;
>>
>>       return Container.First.Element.all; -- <-- RAISES
>>    end First_Element;
> 
> What is Checks? If it is/returns False when the list is empty, you'll try to
> dereference null.

My mistake. That's the code for the container, not your code.

-- 
Jeff Carter
"I wave my private parts at your aunties."
Monty Python & the Holy Grail
13