Re: Generic-Package Elaboration Question / Possible GNAT Bug.

["Yannick Duchêne (Hibou57)" <yannick_duchene@yahoo.fr>]

Le Tue, 22 Nov 2011 22:03:52 +0100, Randy Brukardt <randy@rrsoftware.com>  
a écrit:

> "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> wrote in message
> news:12hfiflyf7pr5$.l3pkpgoid8xt$.dlg@40tude.net...
>  > I my experience at least 40% of my debugging
>> efforts in Ada 95 was spent on catching accessibility checks faults. Ada
>> 2005 improved that greatly. To me this is a vivid example why dynamic
>> checks are evil.
>
> It's not "dynamic checks" that are evil, it is checking the uncheckable  
> that is evil.
That's why C/C++ assertion macros will never value as much: it does not  
even  help to warrant the check, at the time it is done, is valid (just  
forget a hand written assertion check on array bounds, and the later hand  
written assertion check on the value of an item in that array will just be  
random result, and may even fail to trap an error).

I like the view you underline, that not only checks are to prevent invalid  
execution, but also have to ensure checks them-self are valid. Each check  
also warrant the validity of all other checks. In practice, this is more  
safely achieved automatically. Nice point.

-- 
“Syntactic sugar causes cancer of the semi-colons.”  [Epigrams on  
Programming — Alan J. — P. Yale University]
“Structured Programming supports the law of the excluded muddle.” [Idem]