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From: Jacob Sparre Andersen <sparre@nbi.dk>
Newsgroups: comp.lang.ada
Subject: Re: not null
Date: Thu, 05 Mar 2009 18:20:01 +0100
Organization: Jacob Sparre Andersen
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Date: 2009-03-05T18:20:01+01:00
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Adam Beneschan wrote:
> Jacob Sparre Andersen wrote:

>> > Whatever mistakes a programmer could in the actual Ada language
>> > make by forgetting to check whether an access value is null, he
>> > could make in the above example by forgetting to check the
>> > Present discriminant.
>>
>> No.  The _compiler_ checks the discriminant.  The programmer will
>> get a Constraint_Error if he tries to use "Ref" while "Present" is
>> false.
>
> It also checks access values and raises Constraint_Error if they're
> null, so I don't understand what your point is.

Neither do I.  Must have been sleepy.

Greetings,

Jacob
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