Re: [boost] [variant] Basic rvalue and C++11 features support

Subject: Re: [boost] [variant] Basic rvalue and C++11 features support
From: Dave Abrahams (dave_at_[hidden])
Date: 2013-01-08 17:25:25

on Tue Jan 08 2013, "Peter Dimov" <lists-AT-pdimov.com> wrote:

> Nevin Liber wrote:
>> Other than destroyable and (possibly) assignable,
>
> Assignable and move-assignable are an absolute requirement, I'd say. I
> also consider copy and move construction from a moved-from object part
> of the absolute minimum.
>
>> it really is up to the author of the class to define what operations
>> are allowed on moved-from objects.
>
> That's trivially true, because "valid" is always defined by the author
> of the class. But some definitions are more useful than others. 

IMO the issue in this case isn't what definitions are useful, but that
the definition of "valid" was already set before move semantics was
added and it can't be changed without breaking code.

-- 
Dave Abrahams
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