Is std::move() a misleading misnomer?

From	Juha Nieminen <nospam@thanks.invalid>
Newsgroups	comp.lang.c++
Subject	Is std::move() a misleading misnomer?
Date	2022-07-15 12:02 +0000
Organization	Aioe.org NNTP Server
Message-ID	<tarkvv$jc4$1@gioia.aioe.org> (permalink)

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Let's take a relatively simple line of code:

    v1 = std::move(v2);

What does that do? Well, we know for certain (at least if the type of 'v1'
and 'v2' has been logically implemented) that 'v1' will contain what
'v2' contained before this statement.

But what will 'v2' contain?

It depends. (More particularly, it depends on whether the type in
question implements a move assignment operator, and it has been
implemented in the recommended way.)

But should it really depend on anything? Isn't that statement
expressing the desire to *move* the contents of 'v2' into 'v1',
thus leaving 'v2' empty? (Even if under the hood a deep copy
is being done instead, consistency of behavior would dictate
for 'v2' to become empty nevertheless.)

The fact is that if we don't know the type of 'v1' and 'v2'
we cannot assume that 'v2' will be empty.

Since std::move() does not guarantee that the contents will be
moved, isn't it quite a misnomer?

std::to_rvalue() might be more cryptic, but at least it would
express much better what it's actually doing.

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Thread

Is std::move() a misleading misnomer? Juha Nieminen <nospam@thanks.invalid> - 2022-07-15 12:02 +0000
  Re: Is std::move() a misleading misnomer? Bonita Montero <Bonita.Montero@gmail.com> - 2022-07-15 14:43 +0200
  Re: Is std::move() a misleading misnomer? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2022-07-15 06:18 -0700
    Re: Is std::move() a misleading misnomer? Bonita Montero <Bonita.Montero@gmail.com> - 2022-07-15 19:09 +0200
  Re: Is std::move() a misleading misnomer? Bo Persson <bo@bo-persson.se> - 2022-07-15 16:01 +0200
    Re: Is std::move() a misleading misnomer? Juha Nieminen <nospam@thanks.invalid> - 2022-07-16 18:21 +0000
      Re: Is std::move() a misleading misnomer? Bo Persson <bo@bo-persson.se> - 2022-07-16 21:11 +0200
        Re: Is std::move() a misleading misnomer? Juha Nieminen <nospam@thanks.invalid> - 2022-07-17 14:28 +0000
  Re: Is std::move() a misleading misnomer? Gawr Gura <gawrgura@mail.hololive.com> - 2022-07-15 08:34 -0700
  Re: Is std::move() a misleading misnomer? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2022-07-15 16:03 +0000
    Re: Is std::move() a misleading misnomer? Bonita Montero <Bonita.Montero@gmail.com> - 2022-07-15 19:12 +0200
      Re: Is std::move() a misleading misnomer? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2022-07-16 19:24 +0000
  Re: Is std::move() a misleading misnomer? "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2022-07-15 23:08 +0200
  Re: Is std::move() a misleading misnomer? Paavo Helde <eesnimi@osa.pri.ee> - 2022-07-16 11:48 +0300
  Re: Is std::move() a misleading misnomer? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2022-07-16 16:31 -0700
    Re: Is std::move() a misleading misnomer? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2022-07-16 18:32 -0700
      Re: Is std::move() a misleading misnomer? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2022-07-19 16:41 -0700
  Re: Is std::move() a misleading misnomer? wij <wyniijj2@gmail.com> - 2022-07-18 16:14 -0700
    Re: Is std::move() a misleading misnomer? Bonita Montero <Bonita.Montero@gmail.com> - 2022-07-19 07:59 +0200
  Re: Is std::move() a misleading misnomer? Anthony Capobianco <kiiwy112@gmail.com> - 2022-07-20 05:11 -0700
    Re: Is std::move() a misleading misnomer? Paavo Helde <eesnimi@osa.pri.ee> - 2022-07-20 15:26 +0300
    Re: Is std::move() a misleading misnomer? Manfred <noname@add.invalid> - 2022-07-21 01:16 +0200
    Re: Is std::move() a misleading misnomer? "Fred. Zwarts" <F.Zwarts@KVI.nl> - 2022-07-21 09:47 +0200
    Re: Is std::move() a misleading misnomer? Juha Nieminen <nospam@thanks.invalid> - 2022-07-21 09:05 +0000
      Re: Is std::move() a misleading misnomer? Paavo Helde <eesnimi@osa.pri.ee> - 2022-07-21 13:12 +0300
      Re: Is std::move() a misleading misnomer? red floyd <no.spam.here@its.invalid> - 2022-07-21 13:09 -0700
  Re: Is std::move() a misleading misnomer? Andrey Tarasevich <andreytarasevich@hotmail.com> - 2022-07-20 13:08 -0700

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