| // An example of defining a postconstructor for a class which |
| // uses boost::signals2::deconstruct as its factory function. |
| // This example expands on the basic postconstructor_ex1.cpp example |
| // by passing arguments to the constructor and postconstructor. |
| // |
| // Copyright Frank Mori Hess 2009. |
| |
| // Use, modification and |
| // distribution is subject to 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) |
| // For more information, see http://www.boost.org |
| |
| #include <boost/shared_ptr.hpp> |
| #include <boost/signals2/deconstruct.hpp> |
| #include <iostream> |
| #include <sstream> |
| #include <string> |
| |
| namespace bs2 = boost::signals2; |
| |
| namespace mynamespace |
| { |
| class Y |
| { |
| public: |
| /* This adl_postconstruct function will be found |
| via argument-dependent lookup when using boost::signals2::deconstruct. */ |
| template<typename T> friend |
| void adl_postconstruct(const boost::shared_ptr<T> &, Y *y, const std::string &text) |
| { |
| y->_text_stream << text; |
| } |
| void print() const |
| { |
| std::cout << _text_stream.str() << std::endl; |
| } |
| private: |
| friend class bs2::deconstruct_access; // give boost::signals2::deconstruct access to private constructor |
| // private constructor forces use of boost::signals2::deconstruct to create objects. |
| Y(const std::string &text) |
| { |
| _text_stream << text; |
| } |
| |
| std::ostringstream _text_stream; |
| }; |
| } |
| |
| int main() |
| { |
| boost::shared_ptr<mynamespace::Y> y = bs2::deconstruct<mynamespace::Y>("Hello, ").postconstruct("world!"); |
| y->print(); |
| return 0; |
| } |