抱歉，未实现:mangling过载

对于一段据我所知是正确的代码，我得到了这个编译错误(对不起，未实现:mangling overload)。我试图将代码最小化到一个可管理的示例，但它仍然很长(抱歉)。我知道c++ 11的东西在开发中，所以这可能是我的编译器(GCC 4.6.2)的问题，但也可能是我遗漏了一些东西。

模态函数仅仅是更复杂函数(具有不同返回类型)的占位符。实际代码的目的是在一组数据结构上提供索引，以便使用不同的匹配标准进行快速查找。

欢呼马库斯

#include <map>
#include <string>
#include <iostream>
#include <list>
#include <functional>
#include <cassert>
//
// Functions
//
struct mod2 : public std::unary_function<int, int> {
  int operator()(int x) const { return x % 2; }
};
struct mod3 : public std::unary_function<int, int> {
  int operator()(int x) const { return x % 3; }
};
struct mod4 : public std::unary_function<int, int> {
  int operator()(int x) const { return x % 4; }
};

//
// Base class foo
//
struct foo {
  std::vector<int> data_m;
  foo() : data_m() {}
  int& insert(int x) {
    data_m.push_back(x);
    return data_m.back();
  }
  template<typename trans_T>
  std::list<std::pair<typename trans_T::result_type, int> >
  match(const typename trans_T::result_type& pattern,
        const trans_T& trans = trans_T()) const {
    std::list<std::pair<typename trans_T::result_type, int> > results;
    for (auto it = data_m.begin(); it != data_m.end(); ++it) {
      auto p = trans(*it);
      if (pattern == p) {
        results.push_back(std::make_pair(p, *it));
      }
    }
    return results;
  }
};

//
// Derived class bar
//
template<typename base_T, typename trans_T>
struct bar : public base_T {
  typedef base_T base_type;
  typedef std::multimap<typename trans_T::result_type, int> index_type;
  index_type index_m;
  bar(const trans_T& trans = trans_T()) : base_type(), index_m() {}
  int& insert(int x, const trans_T& trans = trans_T()) {
    return index_m.insert(typename index_type::value_type(trans(x), base_type::insert(x)))->second;
  }
  std::pair<typename index_type::const_iterator,
            typename index_type::const_iterator>
  match(const typename trans_T::result_type& pattern,
        const trans_T& trans = trans_T()) const {
    return index_m.equal_range(pattern);
  }
  template<typename xtrans_T>
  decltype(base_type().match(typename xtrans_T::result_type(), xtrans_T()))
  match(const typename xtrans_T::result_type& pattern,
        const xtrans_T& xtrans = xtrans_T()) const {
    return base_type::match(pattern, xtrans);
  }
};

//
// Begin/end functions present in Boost but not in GCC
//
template<typename iter_T>
  iter_T begin(const std::pair<iter_T, iter_T>& range) {
  return range.first;
}
template<typename iter_T>
  iter_T end(const std::pair<iter_T, iter_T>& range) {
  return range.second;
}

//
// Main
//
int main(const int argc, const char** argv) {
  using std::cout;
  using std::endl;
  bar<bar<foo, mod2>, mod3> baz;

  ///
  /// Insert some numbers
  ///
  for (int i = 0; i < 20; ++i) {
    baz.insert(i);
  }
  for (int i = 0; i < 5; ++i) {
    cout << "i = " << i << endl;
    ///
    /// Try to match with different functions
    ///
    auto baz_match_mod2 = baz.match(i, mod2());
    cout << "mod2:";
    for (auto it = begin(baz_match_mod2); it != end(baz_match_mod2); ++it) {
      assert(it->first == i);
      cout << ' ' << it->second;
    }
    cout << endl;
    auto baz_match_mod3 = baz.match(i, mod3());
    cout << "mod3:";
    for (auto it = begin(baz_match_mod3); it != end(baz_match_mod3); ++it) {
      assert(it->first == i);
      cout << ' ' << it->second;
    }
    cout << endl;
    auto baz_match_mod4 = baz.match(i, mod4());
    cout << "mod4:";
    for (auto it = begin(baz_match_mod4); it != end(baz_match_mod4); ++it) {
      assert(it->first == i);
      cout << ' ' << it->second;
    }
    cout << endl;
  }
  return 0;
}