[boost] Rave for proposed Boost.Local (functions)

1 Feb 2011

      Hey everyone,

The purpose of this e-mail is to rave about Lorenzo's proposed 
Boost.Local library in the hopes of inspiring people to start the review 
process for it.  :-)

I have been experimenting with using this library in my own code, and it 
has been a godsend for me.  In one of the projects I have been working 
on I ran into many situations where I needed to call a higher-order 
function with a closure, and the closure was just complicated enough 
that I couldn't use Boost.Lambda.  Before using this library I 
frequently found myself either writing a lot of extra code to 
work-around the need for a higher-order function, or writing a lot of 
boilerplate to create classes that would only be used by a single 
function in order to create a function object.  This library has let me 
write the closures that I need in a fairly painless fashion and so has 
made my life a lot easier!

At first I thought that the interface needed to use it was ugly, but as 
I have gotten used to it I have changed my mind.  Part of why I thought 
it was ugly was because of the way that whitespace was used in the 
example included in the original e-mail:

         BOOST_LOCAL_FUNCTION(
         (void) (add)( (double)(num) (const bind)((factor))  (bind)((&sum))  )
         ) {
             sum += factor * num;
             std::clog<<  "Summed: "<<  sum<<  std::endl;
         } BOOST_LOCAL_FUNCTION_END(add)
         add(100.0);

To my mind this example looks a lot clearer if you reformat it as follows:

         BOOST_LOCAL_FUNCTION(
             (void) (add)(
                 (double)(num)
                 (const bind)((factor))
                 (bind)((&sum))
             )
         ) {
             sum += factor * num;
             std::clog<<  "Summed: "<<  sum<<  std::endl;
         } BOOST_LOCAL_FUNCTION_END(add)
         add(100.0);

I would be happy to volunteer to be the review manager if one is needed 
to move the process along, but since I am new to the community and 
personally biased in favor of the library (though I would endeavor to be 
unbiased as a reviewer) I recognize you all will presumably want someone 
that you all know better and who is more neutral.  Regardless, I hope 
that we can start down the road of incorporating this library into boost 
because I believe it would be of great benefit to the C++ community at 
large.

Cheers,
Greg

[boost] Rave for proposed Boost.Local (functions)

Gregory Crosswhite