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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 16:29:23 -0500
Organization: JSA Research & Innovation
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Xref: reader02.eternal-september.org comp.lang.ada:52294
Date: 2018-05-11T16:29:23-05:00
List-Id: <comp.lang.ada>

"Paul Rubin" <no.email@nospam.invalid> wrote in message 
news:871sejyp8d.fsf@nightsong.com...
> "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:
...
> So you delete all the lists at the same time?

Yes, of course.

> What if you have two
> 5-element lists, (a b x y z) and (c d x y z) where both share the same
> 3-element tail?

That sort of sharing almost never makes sense in an Ada context. Remember 
that each individual list element is mutable, so one has to be able to 
"split" any sharing if a node gets modified. It certainly can be programmed, 
but it would take a relatively rare set of operations for that to be of 
benefit.

                      Randy.