(C++) MultipleInheritanceExample1

 

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++11

Compiler(s):

• G++ 4.9.2

Libraries used:

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

 

 

 

 

 

Qt project file: ./CppMultipleInheritanceExample1/CppMultipleInheritanceExample1.pro

 

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TEMPLATE = app CONFIG += console CONFIG -= app_bundle CONFIG -= qt QMAKE_CXXFLAGS += -std=c++11 -Wall -Wextra -Weffc++ -Werror SOURCES += main.cpp

 

 

 

 

 

./CppMultipleInheritanceExample1/main.cpp

 

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#include <cassert> #include <iostream> #include <memory> #include <string> //Abstract base class struct State {   virtual ~State() {}   virtual const std::string ToStr() const = 0; }; struct StateLoggedIn : public State {   const std::string ToStr() const { return "logged_in"; } }; struct StateNotLoggedIn : public State {   const std::string ToStr() const { return "not_logged_in"; } }; //Abstract base class struct Administrator : public State {   virtual ~Administrator() {} }; struct AdministratorLoggedIn : public Administrator, StateLoggedIn {   const std::string ToStr() const { return this->StateLoggedIn::ToStr(); } }; struct AdministratorNotLoggedIn : public Administrator, StateNotLoggedIn {   const std::string ToStr() const { return this->StateNotLoggedIn::ToStr(); } }; //Abstract base class struct Participant : public State {   virtual ~Participant() {} }; struct ParticipantLoggedIn : public Participant, StateLoggedIn {   const std::string ToStr() const { return this->StateLoggedIn::ToStr(); } }; struct ParticipantNotLoggedIn : public Participant, StateNotLoggedIn {   const std::string ToStr() const { return this->StateNotLoggedIn::ToStr(); } }; int main() {   std::shared_ptr<Administrator> a1(new AdministratorLoggedIn);   std::shared_ptr<Administrator> a2(new AdministratorNotLoggedIn);   std::shared_ptr<Participant> p1(new ParticipantLoggedIn);   std::shared_ptr<Participant> p2(new ParticipantNotLoggedIn);   assert(a1->ToStr() == p1->ToStr());   assert(a2->ToStr() == p2->ToStr());   std::cout << a1->ToStr() << '\n';   std::cout << a2->ToStr() << '\n'; } /* Screen output: logged_in not_logged_in Press <RETURN> to close this window... */