Re: Problem with boost::lambda and pointers

From:
"Peter Dimov" <pdimov@gmail.com>
Newsgroups:
comp.lang.c++.moderated
Date:
28 Aug 2006 08:43:59 -0400
Message-ID:
<1156762474.299903.248490@m73g2000cwd.googlegroups.com>
Carl Barron wrote:

this works only using boost::bind [or tr1::bind] but note the
complexity,
struct my_class
{
   int x;
   my_class(int a):x(a){}
   void func() {std::cout << x << '\n';}
};

typedef std::map<int,boost::shared_ptr<my_class> > Map;
Map m;

std::for_each
   (
      m.begin(),
      m.end(),
      boost::bind
      (
         &my_class::func,
         boost::bind
         (
            &boost::shared_ptr<my_class>::get,
            boost::bind(&Map::value_type::second,_1)
         )
      )
   );

looks a bit messy note three appllications of bind, and if this is done
more than once it is a pain to read, etc.


Two applications of bind are enough.

 std::for_each
    (
       m.begin(),
       m.end(),
       boost::bind
       (
          &my_class::func,
          boost::bind(&Map::value_type::second, _1)
       )
    );

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