(C++) BoostSignals2Example3

 

 

Boost.Signals2 example 3 is a Boost.Signals2 example.

Technical facts

 

Operating system(s) or programming environment(s)

• Lubuntu 15.04 (vivid)

IDE(s):

• Qt Creator 3.1.1

Project type:

• Console application

C++ standard:

• C++98

Compiler(s):

• G++ 4.9.2

Libraries used:

• STL: GNU ISO C++ Library, version 4.9.2

 

 

 

 

 

Qt project file: ./CppBoostSignals2Example3/CppBoostSignals2Example3.pro

 

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include(../../ConsoleApplication.pri) include(../../Libraries/Boost.pri) SOURCES += main.cpp

 

 

 

 

 

./CppBoostSignals2Example3/main.cpp

 

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#include <iostream> #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Weffc++" #pragma GCC diagnostic ignored "-Wunused-local-typedefs" #pragma GCC diagnostic ignored "-Wunused-but-set-parameter" #include <boost/bind.hpp> #include <boost/lambda/lambda.hpp> #include <boost/signals2.hpp> #pragma GCC diagnostic pop //NoIdea is a class that can ask for an answer, but //has no idea what this answer is. It relies on a //Boost.Units2 signal its return value struct NoIdea {   NoIdea() : m_signal{} {}   void Ask()   {     if (m_signal())     {       std::cout << *m_signal() << '\n';     }     else     {       std::cout << "[No one answers]" << '\n';     }   }   boost::signals2::signal<std::string()> m_signal; }; const std::string SayX() { return "The answer"; } int main() {   NoIdea x;   x.Ask();   x.m_signal.connect(&SayX);   x.Ask(); }