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From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Getting the index for an element in mutually referencing
 containers
Date: Wed, 15 Mar 2017 19:59:18 -0700
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Date: 2017-03-15T19:59:18-07:00
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"Randy Brukardt" <randy@rrsoftware.com> writes:
> I don't recall ever needing both "strong" or "weak" references to any data 
> structure.

I've only heard of weakrefs in connection with garbage collected
systems, but they are useful there, for dealing with potentially
circular references between long-lived objects.

> Most structures only need short-lived references, and the ones 
> that need long-lived ones are almost always permanent 

That's partly a matter of how the application is organized, which in
turn is influenced by the language features.  In particular, with GC
available, it suddenly becomes less important to carefully manage object
lifetimes and so you get a mixture.  Of course then it's hard to prove
impossibility of OOM crashes, so this may not be a great approach for
critical realtime systems.  But for lots of other tasks it makes
programming easier at the now-cheap cost of a few more computer
resources.