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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: How to get Ada to ?cross the chasm??
Date: Fri, 11 May 2018 15:46:58 -0500
Organization: JSA Research & Innovation
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Xref: reader02.eternal-september.org comp.lang.ada:52291
Date: 2018-05-11T15:46:58-05:00
List-Id: <comp.lang.ada>

"Niklas Holsti" <niklas.holsti@tidorum.invalid> wrote in message 
news:flkuk5F1ft1U1@mid.individual.net...
...
> However, I don't think this method will free you from worrying about 
> dangling references -- I believe a cursor can be left dangling, just as an 
> access value can be. (I haven't yet had occasion to do such 
> container-centric Ada programming, although I have used the Ada containers 
> in less central roles.)

Correct. However, an implementation can detect dangling cursors if it wants 
to, so (depending on implementation), you could get an exception raised when 
using one (unlike a dangling pointer which does whatever [formally, 
"erroneous execution"]). The main reason that we didn't require dangling 
pointer detection is that a perfect scheme is quite expensive -- but a 
99.99...% detection scheme is reasonably efficient and IMHO should be part 
of every implementation (possibly with some way to turn it off if maximum 
performance is needed).

                                Randy.