Re: [boost] First lambda

From: Aleksey Gurtovoy (agurtovoy_at_[hidden])
Date: 2004-03-06 05:10:03

David Abrahams wrote:
> I just tried using the lambda library for the first time.  Here's
> what came out of it, after some struggle:
> 
>   #include <boost/lambda/lambda.hpp>
>   #include <vector>
>   #include <numeric>
> 
>   using namespace boost::lambda;
> 
>   struct X
>   {
>       X() : count(1) {}
> 
>       unsigned long count;
>   };
> 
>   std::vector<X> xs(10);
>   unsigned long n = std::accumulate(
>       xs.begin(), xs.end(), 0UL,
>       _1 + (&_2) ->* &X::count);

Views make it much cleaner, both conceptually and syntactically:

    unsigned long n = accumulate( 
          transform_view( xs, mem_fn(&X::count) )
        , 0UL
        );
        
--
Aleksey Gurtovoy
MetaCommunications Engineering