(C++) HostClassExample2

 

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: ./CppHostClassExample2/CppHostClassExample2.pro

 

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include(../../ConsoleApplication.pri) #Or use the code below # QT += core # QT += gui # greaterThan(QT_MAJOR_VERSION, 4): QT += widgets # CONFIG   += console # CONFIG   -= app_bundle # TEMPLATE = app # CONFIG(release, debug|release) { #   DEFINES += NDEBUG NTRACE_BILDERBIKKEL # } # QMAKE_CXXFLAGS += -std=c++11 -Wall -Wextra -Weffc++ # unix { #   QMAKE_CXXFLAGS += -Werror # } SOURCES += main.cpp

 

 

 

 

 

./CppHostClassExample2/main.cpp

 

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#include <fstream> #include <iostream> #include <string> template <typename OutputPolicy> struct Tracer : public OutputPolicy { }; struct OutputPolicyCout {   void Trace(const std::string& s)   {     std::cout << s << '\n';   } protected:   ~OutputPolicyCout()   {     // The destructor of a policy class should be protected and non-virtual:     // * Herb Sutter, Andrei Alexandrescu. C++ coding standards: 101 rules,     //   guidelines, and best practices. ISBN: 0-32-111358-6. Item 50: 'Make     //   base class destructors public and virtual, or protected and nonvirtual'     // * Andrei Alexandrescu. Modern C++ Design. 2001. ISBN: 0201704315.     //   Page 13. Section 1.7: 'The lightweight, effective solution that     //   policies should use is to define a nonvirtual protected destructor'   } }; struct OutputPolicyFile {   OutputPolicyFile() : m_file("Trace.txt")   {   }   void Trace(const std::string& s)   {     m_file << s << '\n';   }   std::ofstream m_file; protected:   ~OutputPolicyFile()   {     // The destructor of a policy class should be protected and non-virtual:     // * Herb Sutter, Andrei Alexandrescu. C++ coding standards: 101 rules,     //   guidelines, and best practices. ISBN: 0-32-111358-6. Item 50: 'Make     //   base class destructors public and virtual, or protected and nonvirtual'     // * Andrei Alexandrescu. Modern C++ Design. 2001. ISBN: 0201704315.     //   Page 13. Section 1.7: 'The lightweight, effective solution that     //   policies should use is to define a nonvirtual protected destructor'   } }; int main() {   Tracer<OutputPolicyCout> p1;   Tracer<OutputPolicyFile> p2;   p1.Trace("x");   p2.Trace("x"); }