cpp-cheatsheet/virtual.cpp at main · kubgus/cpp-cheatsheet · GitHub

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#include<iostream>

structEntity
{
virtualvoidPrint()
 {
 std::cout << "Entity" << std::endl;
 }
};

classPlayer : publicEntity// class has private inheritance by default
{
public:
voidPrint() override
 {
 std::cout << m_Name << std::endl;
 }

private:
constchar *m_Name = "Player";
};

classInterface
{
public:
virtualvoidPrint() = 0; // pure virtual function
// makes the class abstract
// must be overridden by derived classes
};

classImplement : publicInterface
{
public:
voidPrint() override
 {
 std::cout << "Hello, World!" << std::endl;
 }
};

intmain()
{

 Entity e;
 e.Print();

 Player p;
 p.Print();

/*Interface i; // can't instantiate abstract class
 i.Print();*/
// can't call pure virtual function

 Implement impl; // can instantiate derived class
 impl.Print(); // can call overridden function
}