On Tue, Nov 29, 2011 at 1:30 PM, Daniel James wrote:

On 29 November 2011 13:09, Robert Jones wrote:

...

In this code (fabricated) sequence, ages_by_bind compiles, but ages_by_lambda does not.

I believe this is because the lambda version does not publish result_type to its resultant functors, since the increased generality of lambda makes this difficult or impossible to do.

Is there any way I can get round this, as it currently makes the lambda/transformed combination completely unusable AFAICS.

Have you tried using Phoenix? It has better support for result_type.

I have now, precisely because I'd understood it had better support as you said. Like this, perhaps someone could tell me if this is fine on 1.44/1.47 too! Thx, - Rob. #include #include #include std::vector<int> ages_by_phoenix( const std::map & people ) { namespace ph = boost::phoenix; namespace arg = boost::phoenix::arg_names; using boost::adaptors::transformed; std::vector<int> result; boost::range::push_back( result, people | transformed( ph::bind( & std::map::value_type::second, arg::_1 ) ) ); return result; }

Michel Morin wrote:

Boost.Lambda has supported result_of since Boost 1.44.

And transformed_iterator has full support of result_of since Boost 1.47. Regards, Michel