shunsuke wrote:

BTW, Boost.Lambda can support result_of without modifying its source code.

#include <boost/lambda/result_of.hpp> // imaginary header for now. namespace bl = boost::lambda;

// result_of conforming FunctionObject bl::bind( bl::constructor< boost::shared_ptr<int> >(), bl::bind(bl::new_ptr<int>(), bl::_1) )

If interested, I think I can upload result_of.hpp.

Sounds good to me - but it isn't up to me to decide. You should probably repost this suggestion with '[lambda]' in the subject or file a feature request with a patch for that library's authors to pick it up. IIRC there was a planned merger of Lambda and Phoenix2. Itseems you have some time to contribute ITM and your "Egg" library showssome experience in that domain. I'm CCing Joel as he might be interested in your help. Getting "Factory functionality" out of the Lambda library does not deprecate the utility we are reviewing: Using Boost.Lambda just to create a single class instance seems sorta wasteful. Factory's greatest strength is its simplicity: We can easily make it compile (and optimize decently) even with legacy compilers and it's lightweight in terms of dependencies and template instantiations. Regards, Tobias