From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
	ip-172-31-65-14.ec2.internal
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=3.0 tests=BAYES_00,T_SCC_BODY_TEXT_LINE
	autolearn=ham autolearn_force=no version=3.4.6
Path: eternal-september.org!reader01.eternal-september.org!.POSTED!not-for-mail
From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Move semantics
Date: Tue, 20 Sep 2022 12:39:44 -0700
Organization: A noiseless patient Spider
Message-ID: <87fsglomwv.fsf@nightsong.com>
References: <e0687b45-9e05-4099-9d63-9278e5dec6f4n@googlegroups.com>
	<tecn59$8s3o$1@dont-email.me> <tecpif$1nnl$1@gioia.aioe.org>
	<tef6oo$rug$1@gioia.aioe.org> <tefg0t$h65$1@gioia.aioe.org>
	<5b429465-6166-4f33-ad1d-3103e4847efcn@googlegroups.com>
	<tg4gt9$5s4b$1@dont-email.me> <868rmfjnx4.fsf@stephe-leake.org>
	<87k05znqpk.fsf@nightsong.com>
	<0b04f763-fa89-4b34-ad52-eb9d57d80d8cn@googlegroups.com>
MIME-Version: 1.0
Content-Type: text/plain
Injection-Info: reader01.eternal-september.org; posting-host="426fc8602af2e2372f9d82205b2e6e6e";
	logging-data="1675196"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX19Yeeq45ITlbLb5UdkfD/tN"
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux)
Cancel-Lock: sha1:Y5yPGSLDxxr8Xum7aR3mEsqRpao=
	sha1:JFMlnBPx+ux6xyesRoBaUoCvzQU=
Xref: reader01.eternal-september.org comp.lang.ada:64372
List-Id: <comp.lang.ada>

AdaMagica <christ-usch.grein@t-online.de> writes:
> What I do not understand: Why should the move operation be less
> expensive than a copy?

Besides avoiding copying indirectly pointed-to data, it also can enforce
single ownership in things like std::unique_ptr.