Re: [boost] [foreach] cheap_copy crisis?

From: Eric Niebler (eric_at_[hidden])
Date: 2005-12-28 13:08:55

MB wrote:
> Eric Niebler wrote:
> 
>>I agree that's not good. I've reimplemented the has_cheap_copy 
>>customization point again. See below.

Just an update on this issue...

BOOST_FOREACH has recently received a face-lift, and this customization 
point has been renamed. It is now called is_lightweight_proxy, which 
refects the fact that this optimization can only legally be applied for 
proxies (like iterator pairs).

In addition, there is a is_noncopyable customization point, which is 
needed to prevent BOOST_FOREACH from generating code that won't compile. 
(If your type derives from boost::noncopyable, is_noncopyable defaults 
to true; it's false otherwise.)

Finally, this is now part of BOOST_FOREACH's documentation. Huzzah.

-- 
Eric Niebler
Boost Consulting
www.boost-consulting.com