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Date: Tue, 20 Sep 2022 04:44:28 -0700 (PDT)
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Subject: Re: Move semantics
From: AdaMagica <christ-usch.grein@t-online.de>
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Paul Rubin schrieb am Montag, 19. September 2022 um 20:50:50 UTC+2:
> I think it refers to the C++ notion. 
> https://en.cppreference.com/w/cpp/utility/move

What I do not understand: Why should the move operation be less expensive than a copy?
As I see it: First you have to do a copy, then delete the source.

>  but also means str might now be empty.

I find this "may be empty" astonishing.