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From: "Alex R. Mosteo" <devnull@mailinator.com>
Newsgroups: comp.lang.ada
Subject: Re: Type safety on wikipedia
Date: Fri, 27 Jan 2006 12:14:11 +0100
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    <43D8B95E.80001@mailinator.com> <drbmr2$ooi$1@geraldo.cc.utexas.edu>
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Date: 2006-01-27T12:14:11+01:00
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Bobby D. Bryant wrote:
> On Thu, 26 Jan 2006, "Alex R. Mosteo" <devnull@mailinator.com> wrote:
> 
> 
>>Martin Krischik wrote:
>>
>>>Hello
>>>
>>>I found this interesting article on Wikipedia which made me think a
>>>bit:
>>>
>>>http://en.wikipedia.org/wiki/Type_safety
>>>
>>>Do have a look at the talk page as well.
>>
>>After reading that I'm not sure how Ada can be type safe if unchecked 
>>deallocation is a common way of implementing relatively common tasks as 
>>linked lists and so. The explicit example given for "type unsafety" is 
>>easily doable in Ada.
>>
>>But I acknowledge that I'm new to the topic, anyone can explain?
> 
> 
> The Unchecked_Deallocation has to be instantiated for a specific type.
> Is there a way of using it that isn't type safe?  (Surely it isn't the
> type that's "Unchecked" ?)

If I've understood things correctly, the problem isn't that UD is typed, 
but that once you start manipulating heap pointers by hand, you're out 
of the game (due to dangling pointers and so).

But then, I'm talking by hearsay from wikipedia sources that I don't 
really trust. The last post from Florian seems to point that the problem 
is much more fundamental (again, if IIUTC).