On 05/05/2011 01:37, Raffi Enficiaud wrote:

Hi all,

Sorry for bothering with this. I recently encountered some problems in using boost.lambda with Visual 2010 Express, and need some clues for solving the issue (there are many ways around of course). I simply want to accumulate the values of a std::map, and I thought using lambda to access the second member of the map iterator was appropriate. Here is the piece of code:

typedef std::map<T1, unsigned short> m_t; m_t m ; // fill m double acc(0); std::for_each(m.begin(), m.end(), var(acc) +=& _1->*& m_t::value_type::second);

The last line does not compile on Visual (it does on GCC), I have to add a typedef:

typedef typename m_t::value_type aa; std::for_each(m.begin(), m.end(), var(acc) +=& _1->*& aa::second);

Which one is "more correct" ?

It's one of the annoying MSVC bugs. MSVC doesn't like it when you chain nested names in template contexts.