我目前正在编写一个弱引用资源管理器，如下所示，编译器抱怨管理器有一个私有构造函数。
我的问题是：为什么我无法访问静态函数中的私有成员函数？
#ifndef TENSOR_MANAGER_H
#define TENSOR_MANAGER_H
#include <memory>
#include <functional>
#include <map>
#include <iostream>
template<typename key_t, typename model_t>
class Manager : public std::enable_shared_from_this<Manager<key_t, model_t> > {
public:
using self_t = Manager<key_t, model_t>;
public:
static auto Create() {
return std::make_shared<self_t>();
}
public:
std::shared_ptr<model_t> GetOrAdd(const key_t &&key, const char *data, size_t size) {
auto pos = m_resources.find(key);
std::shared_ptr<model_t> tmp;
if (pos != m_resources.end()) {
tmp = pos->second.lock();
}
if (!tmp) {
model_t *p = new model_t();
auto deletor = std::bind(&self_t::releaseItem,
std::weak_ptr<self_t>(this->shared_from_this()),
key,
std::placeholders::_1);
tmp = std::shared_ptr<model_t>(p, deletor);
m_resources[key] = std::weak_ptr<model_t>(tmp);
}
return tmp;
}
public:
void Print() {
std::cout << "Content: ";
for (const auto &item : m_resources) {
std::cout << item.first << " ";
}
std::cout << std::endl;
}
private:
static void releaseItem(std::weak_ptr<self_t> self, const key_t &key, model_t *p) {
std::shared_ptr<Manager<key_t, model_t>> mgr = self.lock();
if (mgr) {
mgr->m_resources.erase(key);
}
delete p;
}
private:
std::map<key_t, std::weak_ptr<model_t> > m_resources;
Manager() = default;
};
#endif //TENSOR_MANAGER_H
现在编译器给出错误：
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include/c++/v1/memory:2043:66: error: field of type 'Manager<std::__1::basic_string<char>, int>' has private default constructor
_LIBCPP_INLINE_VISIBILITY constexpr __compressed_pair_elem() : __value_() {}
