Re: [boost] [move][container] Fast-track reviews for Move and Container?

Subject: Re: [boost] [move][container] Fast-track reviews for Move and Container?
From: Frank Mori Hess (frank.hess_at_[hidden])
Date: 2009-08-17 16:16:56

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On Monday 17 August 2009, Thomas Klimpel wrote:
> > Type & operator=(BOOST_RV_REV(Type) t)
> > {
> >    Type tmp(boost::move(t));
> >    this->swap(tmp);
> > }
>
> I hope I can omit the temporary, because two calls to swap are less
> efficient than a single call to swap. I can't find any second thought that
> forces me to create a temporary. Do I miss something?

I don't think you need to.  The temporary is useful if you want to always give 
moved-from objects a specific state (presumably the move constructor does 
this).  But the standard is looser, it only requires the moved-from object 
doesn't violate any of the class invariants.

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