Hello, I am in the process of converting an application that uses raw pointers to boost::shared_ptr. For example: ErrorWriter *writer_; now becomes: typedef boost::shared_ptr<ErrorWriter> ErrorWriterPtr; ErrorWriterPtr writer_; The problem is that, with raw pointers I was able to use 0-value pointers in the constructor, like so: Parser(ErrorWriter *writer) : writer_(writer) { } Parser testParser(0); So it was possible to initialize the class with an empty writer pointer, and then later in some other Parser code do this: if (writer_ == 0) { /* create default error writer */ } But now, with shared_ptr, I cannot assign or evaluate to 0. I understand that the default ErrorWriterPtr constructor and ErrorWriterPtr.reset() will provide me with an empty pointer that I can check like so: if (writer_.get() == 0) { /* create default error writer */ } But how do I rewrite the Parser constructor to fit this new idiom? If I have: Parser(ErrorWriterPtr writer) : writer_(writer) { } What is the equivalent to: Parser testParser(0); Thank you for any assistance! Best, Scott