Use of deleted copy constructor in the singleton
c++, c++11, c++14, singleton
Solution
Consider what you're trying to do here:
Settings_manager set = Settings_manager::get_instance();
You have your singleton, `get_instance()`, and you're trying to copy it? That would kind of defeat the purpose of singleton if you could just... create two of them right?
You want to take a reference:
Settings_manager& set = Settings_manager::get_instance();
This way, `set` is the singleton instance. Not a copy of it.
Problem
I've implemented the singleton pattern like this, there is my code: header file: ``` class Settings_manager{ public: static Settings_manager& get_instance(); void operator=(Settings_manager const&) =delete; Settings_manager(Settings_manager const&) =delete; ... private: Settings_manager(); }; ``` implementation: ``` Settings_manager& Settings_manager::get_instance() { static Settings_manager instance; return instance; } Settings_manager::Settings_manager() { read_file(); } ``` When I try use `get_instance` function in `main` like this: ``` Settings_manager set = Settings_manager::get_instance(); ``` or `Settings_manager set = std::move(Settings_manager::get_instance());` I get ``` error: use of deleted function 'Settings_manager::Settings_manager(const Settings_manager&)' Settings_manager set = Settings_manager::get_instance(); ``` Can somebody tell, what's wrong and explain it? Thanks.