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From: "Randy Brukardt" <randy@rrsoftware.com>
Subject: Re: Getting the index for an element in mutually referencing containers
Date: Wed, 15 Mar 2017 15:12:24 -0500
Date: 2017-03-15T15:12:24-05:00	[thread overview]
Message-ID: <oac779$ffo$1@franka.jacob-sparre.dk> (raw)
In-Reply-To: oaausp$ddn$1@gioia.aioe.org

"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> wrote in message 
news:oaausp$ddn$1@gioia.aioe.org...
> On 2017-03-14 21:40, Randy Brukardt wrote:
...
> The problem is that the smart pointer type must be anonymous (ad-hoc) like 
> access T is. Otherwise, you get the problem of parallel type hierarchies 
> of the targets and the pointers. And the pointer type must have the 
> interface of the target AKA implicit dereference.

The problem of parallel type hierarchies is one that MUST be solved if one 
is going to program with hierarchies. It IS fundamental to strong typing, 
unlike most of these other issues. We really need a solution to it (I've 
tried some and intend to try more).

I don't recall ever needing both "strong" or "weak" references to any data 
structure. Most structures only need short-lived references, and the ones 
that need long-lived ones are almost always permanent (only changed between 
runs). Maybe that's because when the only tool you have is an access type, 
every reference looks unchecked and dangerous. :-) But I doubt that many 
problems need or care about the both possibilities.

                          Randy.



  reply	other threads:[~2017-03-15 20:12 UTC|newest]

Thread overview: 33+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-03-09 13:45 Getting the index for an element in mutually referencing containers Mart van de Wege
2017-03-09 15:25 ` Egil H H
2017-03-09 15:45   ` Mart van de Wege
2017-03-09 16:02     ` Mart van de Wege
2017-03-09 16:11     ` Egil H H
     [not found] ` <ly7f3xedp4.fsf@pushface.org>
     [not found]   ` <86k27xpikd.fsf@gaheris.avalon.lan>
     [not found]     ` <lywpbxc9my.fsf@pushface.org>
     [not found]       ` <86wpbxneuz.fsf@gaheris.avalon.lan>
     [not found]         ` <o9vcbp$t0t$1@franka.jacob-sparre.dk>
2017-03-11  6:45           ` Mart van de Wege
2017-03-11  8:40           ` Simon Wright
2017-03-11  8:58             ` Dmitry A. Kazakov
2017-03-11 11:21               ` Simon Wright
2017-03-11 14:18                 ` Dmitry A. Kazakov
2017-03-11 20:05                   ` Simon Wright
2017-03-11 20:52                     ` Dmitry A. Kazakov
2017-03-11 21:46                       ` Simon Wright
2017-03-11 22:37                         ` Niklas Holsti
2017-03-12  8:22                           ` Simon Wright
2017-03-12  9:38                             ` G.B.
2017-03-12 11:21                               ` Simon Wright
2017-03-13 10:29                             ` Alejandro R. Mosteo
2017-03-12  8:20                         ` Dmitry A. Kazakov
2017-03-12 11:30                           ` Simon Wright
2017-03-12 11:55                             ` Dmitry A. Kazakov
2017-03-12 16:44                               ` Simon Wright
2017-03-12 17:42                                 ` Dmitry A. Kazakov
2017-03-13 19:55                                   ` Randy Brukardt
2017-03-13 20:53                                     ` Dmitry A. Kazakov
2017-03-14 20:40                                       ` Randy Brukardt
2017-03-15  8:44                                         ` Dmitry A. Kazakov
2017-03-15 20:12                                           ` Randy Brukardt [this message]
2017-03-16  2:59                                             ` Paul Rubin
2017-03-16  9:04                                             ` Dmitry A. Kazakov
2017-03-13 23:25                                   ` Simon Wright
2017-03-14  8:25                                     ` Dmitry A. Kazakov
2017-03-12  1:36             ` Randy Brukardt
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