Re: [Boost-users] [phoenix] or [lamdba] Operating on containers of smart pointers.

23 Oct 2008


      AMDG

Raindog wrote:
...
I ran into a problem while cleaning up some old code. What I wanted to 
do was replace explicit for loops with some stl algorithms or 
BOOST_FOREACH. Below is the original function:
|//in header file:
..snip
typedef std::vector chunk_vec_t
chunk_vec_t chunks;
..snip
//in source file:
uint32_t ADT::get_connectivity_data( std::vector< std::vector
...
&output )
{
       output.resize(chunks.size());
       for(chunk_vec_t::iterator it = chunks.begin(); it < 
chunks.end(); ++it)
       {
               uint32_t success = 
(*it)->get_connectivity_data(output[it-chunks.begin()]);
       }
       return TRUE;
}
I think what you want is a two argument version of for_each.

#include 
#include 
#include 
#include 
#include <vector>

typedef std::vectorboost::uint8_t out_t;

struct ADTChunk {
    boost::uint32_t get_connectivity_data(out_t& output) {
        return(0);
    }
};

typedef std::vector chunk_vec_t;
chunk_vec_t chunks;

template
F for_each(Iter1 begin1, Iter1 end1, Iter2 begin2, F f) {
    for(; begin1 != end1; ++begin1, ++begin2) {
        f(*begin1, *begin2);
    }
    return(f);
}

boost::uint32_t get_connectivity_data(std::vector &output)
{
    using namespace boost::lambda;
    output.resize(chunks.size());
    for_each(chunks.begin(), chunks.end(), output.begin(),
        bind(&ADTChunk::get_connectivity_data, *_1, _2));
    return 1;
}

In Christ,
Steven Watanabe