From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham
	autolearn_force=no version=3.4.4
X-Google-Thread: 103376,55f6e230b02eff2f
X-Google-Attributes: gid103376,public,usenet
X-Google-Language: ENGLISH,ASCII-7-bit
Path: 
 g2news2.google.com!postnews.google.com!19g2000hsx.googlegroups.com!not-for-mail
From: Matthew Heaney <mheaney@on2.com>
Newsgroups: comp.lang.ada
Subject: Re: Containers - nontrivial element access
Date: Tue, 02 Oct 2007 09:47:01 -0700
Organization: http://groups.google.com
Message-ID: <1191343621.111082.202400@19g2000hsx.googlegroups.com>
References: <1191275759.184463.238350@n39g2000hsh.googlegroups.com>
   <fdsait$bi2$1@jacob-sparre.dk>
NNTP-Posting-Host: 66.162.65.129
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
X-Trace: posting.google.com 1191343621 9746 127.0.0.1 (2 Oct 2007 16:47:01
 GMT)
X-Complaints-To: groups-abuse@google.com
NNTP-Posting-Date: Tue, 2 Oct 2007 16:47:01 +0000 (UTC)
In-Reply-To: <fdsait$bi2$1@jacob-sparre.dk>
User-Agent: G2/1.0
X-HTTP-UserAgent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US;
 rv:1.8.1.7) Gecko/20070914 Firefox/2.0.0.7,gzip(gfe),gzip(gfe)
Complaints-To: groups-abuse@google.com
Injection-Info: 19g2000hsx.googlegroups.com; posting-host=66.162.65.129;
   posting-account=ps2QrAMAAAA6_jCuRt2JEIpn5Otqf_w0
Xref: g2news2.google.com comp.lang.ada:2250
Date: 2007-10-02T09:47:01-07:00
List-Id: <comp.lang.ada>

On Oct 1, 10:34 pm, "Randy Brukardt" <ra...@rrsoftware.com> wrote:

> Why don't you just use the Swap operation of the containers? One would
> presume that it is implemented as efficiently as possible. (Surely if you
> are using the indefinite version of the containers, it would just be a
> pointer swap; might be a copy with the definite version of vectors, but that
> couldn't be avoided as the object order is significant in that sort of
> implementation.)

But he's trying to swap one component of a element (which happens to
be a record).  The swap operation for container swaps entire elements,
which is not what he wants.

> That surely seems better than using explicit pointers; in most cases,
> worries about efficiency are premature (and when they're not, you probably
> shouldn't be using the predefined containers anyway).

Agreed, you certainly don't need explicit pointers to solve thish
problem.  The solution I showed in my earlier post does exact what the
C++ solution does; there is no effciciency issue.