(C++) TemplateFunctionExample3

 

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: ./CppTemplateFunctionExample3/CppTemplateFunctionExample3.pro

 

---

TEMPLATE = app CONFIG += console CONFIG -= app_bundle CONFIG -= qt SOURCES += main.cpp \     data.cpp HEADERS += \     data.h CONFIG(release, debug|release) {   DEFINES += NDEBUG } QMAKE_CXXFLAGS += -std=c++11 -Wall -Wextra -Weffc++ unix {   QMAKE_CXXFLAGS += -Werror } win32 {   INCLUDEPATH += \     ../../Libraries/boost_1_54_0 }

 

 

 

 

 

./CppTemplateFunctionExample3/data.h

 

---

#ifndef DATA_H #define DATA_H #include <string> struct Data {   Data(const int i, const double d, const std::string& s);   int m_int;   double m_double;   std::string m_string; }; template <class T> const T& Get(const Data&); template <> const int& Get<int>(const Data& d); template <> const double& Get<double>(const Data& d); template <> const std::string& Get<std::string>(const Data& d); #endif // DATA_H

 

 

 

 

 

./CppTemplateFunctionExample3/data.cpp

 

---

#include "data.h" #include <cassert> Data::Data(const int i, const double d, const std::string& s)   : m_int(i), m_double(d), m_string(s) {   assert(Get<int>(*this) == m_int);   assert(Get<double>(*this) == m_double);   assert(Get<std::string>(*this) == m_string); } template <> const int& Get<int>(const Data& d) { return d.m_int; } template <> const double& Get<double>(const Data& d) { return d.m_double; } template <> const std::string& Get<std::string>(const Data& d) { return d.m_string; }

 

 

 

 

 

./CppTemplateFunctionExample3/main.cpp

 

---

#include <cassert> #include <cmath> #include <string> #include "data.h" int main() {   const double x = 123.456;   const Data d(42,x,"Hello world");   assert(Get<int>(d) == 42);   assert(Get<double>(d) == x);   assert(Get<std::string>(d) == "Hello world"); }