[boost] Re: Swapability of named objects?

From: David Abrahams (dave_at_[hidden])
Date: 2003-11-04 13:54:13

Daniel Spangenberg <dsp_at_[hidden]> writes:

> David Abrahams schrieb:
>
>> Daniel Spangenberg <dsp_at_[hidden]> writes:
>>
>> You'd better supply a careful definition of Swappable before I
>> believe that.  Once Howard Hinnant's LWG issue 301 changes are
>> accepted, the picture may look a bit different.
>
> Hmmh, I cannot relate LWG issue 301 to this point of question or even
> Howard Hinnant related to this ;-)
>
> Maybe you mean your **own** issue 227
>
> http://anubis.dkuug.dk/jtc1/sc22/wg21/docs/lwg-defects.html#227
>
> ?

Nope.

> But I see no connection to my point, which is obviously related to
> my missing definition of Swappable. This terminus cannot be found
???----------------------------------------^^^^^^^^
> in C++98, nor could I find any definition on the pages of the commitee.
>
> OK, I mean by swappable that this type provides a swap member
> function.

Oh!  That's the last thing I expected!  So ints are not Swappable.
Now, are there any restrictions on the signature of that function or
its semantics?

> I do not see any connection between swapable and copyable. 

Given *your* (partial) definition of Swappable there is no connection.
I don't happen to think it's a very useful definition, though.

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com