头文件
boost/noncopyable.hpp作用
noncopyable能让继承它的子类，不具备 拷贝构造及赋值构造 的功能。
举例
#include <boost/noncopyable.hpp>
#include <iostream>
// This program demonstrates compiler errors resulting from trying to copy
// construct or copy assign a class object derived from class noncopyable.
namespace
{
class DontTreadOnMe : private boost::noncopyable
{
public:
DontTreadOnMe() { std::cout << "defanged!" << std::endl; }
}; // DontTreadOnMe
} // unnamed namespace
int main()
{
DontTreadOnMe object1;
DontTreadOnMe object2(object1);
object1 = object2;
return 0;
} // main以上代码，编译不通过。
源代码
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