220 8325 <52C4339B.20701@gmail.com> article
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From: Matthew Woehlke <mwoehlke.floss@gmail.com>
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Subject: Re: Proposal: Default swap operation
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On 2013-12-31 21:05, fmatthew5876@gmail.com wrote:
> On Tuesday, December 31, 2013 8:53:46 PM UTC-5, Billy O'Neal wrote:
>> The other issue here is that "using std::swap" would require including
>> <algorithm>...
>
> Implementing swap yourself in this way requires the same.

I think the problem here is that the *header* would need to include it.

Related to that note, I wonder if we should allow e.g.:

foo.h
-----
class Foo
{
   ...
   ~Foo();
   ...
}

foo.cpp
-------

Foo::~Foo() = default;


IOW, allow uses of '= default' after declaration, to allow the compiler 
to emit the default implementation at the source level rather than the 
header level. This would be great for classes where the default 
implementation would require a complete declaration of a type that 
otherwise could be forward declared. (Especially thinking of 
'unique_ptr<Private>', for which the dtor needs the definition of 
Private, but otherwise Private could be forward declared.)

In this case, this would solve needing <algorithm> in the header.

-- 
Matthew

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