[newbie] curlpp functor

Bonjour,

Je débute en C++. J'essaye d'écrire un petit programme utilisant CulrPP
et j'ai un probleme avec la classe cURLpp::Types::WriteFunctionFunctor

je la définit comme suit
cURLpp::Types::WriteFunctionFunctor functor(WriteMemoryCallback);

et la fonction WriteMemoryCallback :
size_t WriteMemoryCallback(char* ptr, size_t size, size_t nmemb) {
string strTmp(ptr,size);
buffer += strTmp;
return size*nmemb;
};

Ca fonctionne très bien tant que WriteMemoryCallback est une simple
fonction. Par contre, si je l'encapsule dans une classe, GCC me renvoie :
g++ -Wall -O2 -I/usr/include -c ButineurVirtuel.cpp -o
obj/Release/ButineurVirtuel.o
ButineurVirtuel.cpp: In member function «std::string
ButineurVirtuel::load(std::string)»:
ButineurVirtuel.cpp:22: erreur: no matching function for call to
«utilspp::Functor<unsigned int, utilspp::tl::TypeList<char*,
utilspp::tl::TypeList<unsigned int, utilspp::tl::TypeList<unsigned int,
utilspp::NullType> > > >::Functor(<unknown type>)»
/usr/local/include/utilspp/functor/Functor.inl:29: note: candidats sont:
utilspp::Functor<R, TList>::Functor(Fun) [with Fun = size_t
(ButineurVirtuel::*)(char*, size_t, size_t), R = unsigned int, TList =
utilspp::tl::TypeList<char*, utilspp::tl::TypeList<unsigned int,
utilspp::tl::TypeList<unsigned int, utilspp::NullType> > >]
/usr/local/include/utilspp/functor/Functor.inl:40: note:
utilspp::Functor<R, TList>::Functor(const utilspp::Functor<R, TList>&)
[with R = unsigned int, TList = utilspp::tl::TypeList<char*,
utilspp::tl::TypeList<unsigned int, utilspp::tl::TypeList<unsigned int,
utilspp::NullType> > >]
Process terminated with status 1 (0 minutes, 7 seconds)
3 errors, 0 warnings

D'avance merci,
TSalm




Les codes complets: Le premier listing fonctionne, l'autre non:
=========================DEBUT=============================
#include "main.h"
#include <curlpp/cURLpp.hpp>
#include <curlpp/Easy.hpp>
#include <curlpp/Options.hpp>
#include <curlpp/Exception.hpp>

#define MESS(x) std::cout << x << std::endl

using namespace std;
using namespace cURLpp;

#define MAX_FILE_LENGTH 20000

std::string Buffer;

// Muss statisch sein, sonst schlägt das linken fehl
size_t WriteMemoryCallback(char* ptr, size_t size, size_t nmemb)
{
Buffer += ptr;
return size*nmemb;
};


void print()
{
std::cout << "Length: " << std::endl << Buffer.length() << std::endl;
std::cout << "Content: " << std::endl << Buffer << std::endl;
}


int main(int argc, char *argv[])
{
if(argc != 2) {
std::cerr << "Example 05: Wrong number of arguments" << std::endl
<< "Example 05: Usage: example05 url"
<< std::endl;
return EXIT_FAILURE;
}
char *url = argv[1];

try {
cURLpp::Cleanup cleaner;
cURLpp::Easy request;

// Das writer-Callback setzten, damit
// cURL in einen std::string schreibt
cURLpp::Types::WriteFunctionFunctor functor(WriteMemoryCallback);
cURLpp::Options::WriteFunction *test = new
cURLpp::Options::WriteFunction(functor);
request.setOpt(test);

// Die URL setzten, die emfangen werden soll
request.setOpt(new cURLpp::Options::Url(url));
request.setOpt(new cURLpp::Options::Verbose(false));
request.perform();

//print();
}
catch ( cURLpp::LogicError & e ) {
std::cout << e.what() << std::endl;
}
catch ( cURLpp::RuntimeError & e ) {
std::cout << e.what() << std::endl;
}
}
=========================FIN=============================


=========================DEBUT(ne fonctionne pas)========
#include <iostream>
#include <string>

#include <curlpp/cURLpp.hpp>
#include <curlpp/Easy.hpp>
#include <curlpp/Options.hpp>
#include <curlpp/Exception.hpp>


class ButineurVirtuel {
private:
std::string buffer;

public:
ButineurVirtuel();

std::string load(std::string url);

~ButineurVirtuel();

private:
size_t WriteMemoryCallback(char*, size_t , size_t );
cURLpp::Cleanup cleaner;
cURLpp::Easy request;

};


using namespace std;

// constructeur
ButineurVirtuel::ButineurVirtuel() {
buffer = "";
};

//// fonction interne
size_t ButineurVirtuel::WriteMemoryCallback(char* ptr, size_t size,
size_t nmemb) {
string strTmp(ptr,size);
buffer += strTmp;
return size*nmemb;
};

// charge la page :
std::string ButineurVirtuel::load(std::string url) {
buffer = "";


cURLpp::Types::WriteFunctionFunctor functor(WriteMemoryCallback);
cURLpp::Options::WriteFunction *test = new
cURLpp::Options::WriteFunction(functor);
request.setOpt(test);

request.setOpt(new cURLpp::Options::Url(url));
request.setOpt(new cURLpp::Options::Verbose(false));
request.perform();

//delete test;

return buffer;
};

// destructeur :
ButineurVirtuel::~ButineurVirtuel() {}


int main() {
cout << "hello" << endl;
};

=========================FIN=============================