I tried the following example (taken from
http://boost.org/libs/lambda/doc/ar01s05.html#sect:construction_and_destruction) ,
and it failed to compile:

  std::vector<int>  x(10);
  std::vector<int>  y(10);
  std::vector<std::pair<int, int>  > pairs;
  std::transform(x.begin(), x.end(), y.begin(), std::back_inserter(pairs),
    boost::bind(boost::lambda::constructor<std::pair<int, int>  >(), _1,
_2));


Compiling...
main.cpp
c:\dev\boost-1.30.2\boost\bind.hpp(60) : error C2039: 'result_type' : is not
a member of 'boost::lambda::constructor<T> '
        with
        [
            T=std::pair<int,int> 
        ]
        c:\dev\boost-1.30.2\boost\bind\bind_template.hpp(16) : see reference
to class template instantiation 'boost::_bi::result_traits<R,F> ' being
compiled
        with
        [
            R=boost::_bi::unspecified,
            F=boost::lambda::constructor<std::pair<int,int> >
        ]
        c:\dev\projects\boost\main.cpp(67) : see reference to class template
instantiation 'boost::_bi::bind_t<R,F,L> ' being compiled
        with
        [
            R=boost::_bi::unspecified,
            F=boost::lambda::constructor<std::pair<int,int> >,

L=boost::_bi::list2<boost::_bi::list_av_2<boost::arg<1> ,boost::arg<2>>::B1,b
oost::_bi::list_av_2<boost::arg<1> ,boost::arg<2>>::B2>
        ]
c:\dev\boost-1.30.2\boost\bind.hpp(60) : error C2146: syntax error : missing
';' before identifier 'type'
c:\dev\boost-1.30.2\boost\bind.hpp(60) : error C2955: 'boost::_bi::type' :
use of class template requires template argument list
        c:\dev\boost-1.30.2\boost\bind.hpp(92) : see declaration of
'boost::_bi::type'
c:\dev\boost-1.30.2\boost\bind.hpp(60) : fatal error C1903: unable to
recover from previous error(s); stopping compilation

----
In boost/lambda/construct.hpp, I added the following line, and it worked:

template<class T>  struct constructor {

  template <class U>  struct sig { typedef T type; };
+  typedef T result_type;

  T operator()() const {
    return T();
  }
  ...

HTH,
--craig



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