C++ 知道禁用 copy-ctor/assign operator 是 C++ 程序员的试金石

• 陈硕优快云博客 ：知道禁用 copy-ctor/assign operator 是 C++ 程序员的试金石

• vgxpm的专栏：C++之实现禁用 copy-ctor/assign operator ： 对其进行了解释，详细阅读

• 陈硕github/muduo : Singleton.h 的实现中对其对copy-ctor/assign operator进行禁用，利用继承noncopyable，代码： class Singleton : boost::noncopyable

• boost/core/noncopyable.hpp

//  Boost noncopyable.hpp header file  --------------------------------------//

//  (C) Copyright Beman Dawes 1999-2003. Distributed under the Boost
//  Software License, Version 1.0. (See accompanying file
//  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

//  See http://www.boost.org/libs/utility for documentation.

#ifndef BOOST_CORE_NONCOPYABLE_HPP
#define BOOST_CORE_NONCOPYABLE_HPP

#include <boost/config.hpp>

namespace boost {

//  Private copy constructor and copy assignment ensure classes derived from
//  class noncopyable cannot be copied.

//  Contributed by Dave Abrahams

namespace noncopyable_  // protection from unintended ADL
{
  class noncopyable
  {
  protected:
#if !defined(BOOST_NO_CXX11_DEFAULTED_FUNCTIONS) && !defined(BOOST_NO_CXX11_NON_PUBLIC_DEFAULTED_FUNCTIONS)
      BOOST_CONSTEXPR noncopyable() = default;
      ~noncopyable() = default;
#else
      noncopyable() {}
      ~noncopyable() {}
#endif
#if !defined(BOOST_NO_CXX11_DELETED_FUNCTIONS)
      noncopyable( const noncopyable& ) = delete;
      noncopyable& operator=( const noncopyable& ) = delete;
#else
  private:  // emphasize the following members are private
      noncopyable( const noncopyable& );
      noncopyable& operator=( const noncopyable& );
#endif
  };
}

typedef noncopyable_::noncopyable noncopyable;

} // namespace boost

#endif  // BOOST_CORE_NONCOPYABLE_HPP