在 C++ 中使用流运算符<< 和 std：：endl

问：

我正在尝试以下C++类，以使用流运算符<<来记录此答案中的内容：

class Log
{
public:
    Log()
        : m_filename( "dafault.log" )
    {}

    // if you wanna give other names eventually...
    Log( const std::string & p_filename )
        : m_filename( p_filename )
    {}

    virtual ~Log()
    {
        // implement  your writeToFile() with std::ofstream 
        writeToFile( m_filename, m_stream, true );
    } 

    template< typename T >
    Log & operator<<( const T & p_value )
    {
        m_stream << p_value;
        return *this;
    }

private:
    std::string         m_filename;
    std::ostringstream  m_stream;
};

这适用于许多情况。但是，它在尝试流式传输时无法编译，std::endl

Log( "/tmp/my.log" ) << 1 << std::endl;

，给出如下错误：

/usr/include/c++/7/string_view:558:5: note:   template argument deduction/substitution failed:
My.cpp:375:36: note:   'Log' is not derived from 'std::basic_ostream<_CharT, _Traits>'
  Log( "/tmp/my.log" ) << 1 << std::endl;
                                    ^~~~

如何让它也一起工作？std:endl