On 10/17/2010 11:32 AM, Dave Abrahams wrote:
On Oct 16, 2010, at 8:37 PM, Eric Niebler<eric@boostpro.com> wrote:
n 10/16/2010 4:41 PM, Mathias Gaunard wrote:
I thought V2 doesn't follow the result_of protocol,
True.
and didn't do perfect forwarding either.
I don't think v3 will do perfect forwarding either. At least not with C++03. It's just too expensive at compile time.
You could approximate it for up to 3-5 arguments. But you can't actually do it perfectly in C++03 even for 1 argument because you will erase rvalue-ness no matter what.
Yeah, that's what we do for 03. Let's call it less-than-perfect forwarding. It's the best we can do. Right now we have a PP constant for that. Mind you, even 3 args is still quite expensive! Then we have 2 more PP constants for all refs and another for all const refs. Regards, -- Joel de Guzman http://www.boostpro.com http://spirit.sf.net