Boost : Error : 2 overloads have similar conversions

Question

Hi,

I'm basically brand new to using Boost. I'm trying to use a ptr_vector to handle some objects that I created.

Specifically I have defined a class Location which defines a particular node on a map (simple 2D game layout). I defined a ptr_vector to hold a set of Locations that have value to the calling function (nodes with units on them). In code :

  boost::ptr_vector<Location> find_targets(int b_hash) {
     boost::ptr_vector<Location> targets;
     //find a node with variables row and col defining its position
     targets.push_back(new Location(row,col));
     //find and push more targets
     return targets;
 }

When I attempt to compile this, even without calling that function, I get the following error :

error C2666: 'boost::scoped_array::operator []' : 2 overloads have similar conversions boost\ptr_container\detail\scoped_deleter.hpp 81

Anyone have any ideas? I couldn't find any relevant help online, but I'll keep looking in the mean-time.

EDIT : More details

I'm using Boost 1.43.0 on Visual Studio 2005.

This is the simplest test I could make that would give this error.

    #include "Location.h"
    #include <boost\ptr_container\ptr_vector.hpp>

    boost::ptr_vector<Location> find_targets()
    {
        boost::ptr_vector<Location> targets;
        targets.push_back(new Location(1,1));
        targets.push_back(new Location(2,1));

        return targets;
    }

    int main(int argc, char **argv)
    {
        boost::ptr_vector<Location> t = find_targets();
    }

And the Location class

class Location {

  // variables //
    private :
        int _row;
        int _col;
    public :


  // functions //
    private :

    public :
       Location() {_row = 0;_col = 0;}
        Location(int r, int c) { _row = r; _col = c;}
       ~Location(){};
        int get_row() {return _row;}
        int get_col() {return _col;}
};

The error occurs with any ptr_vector for any type T that I use. It only happens when I attempt to return a ptr_vector. It works if I return a ptr_vector*, so I'm experimenting with a wrapper class to see if that solves the issue.

Answer 1

That's not reproducible when using Boost 1.43 and VC2005. In order to try it out I added a dummy class Location (you didn't provide it with your code):

struct Location { Location(int, int) {} };

That makes me believe it's an issue with your class Location. Could you provide its definition?