Created
May 18, 2023 13:11
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Vector of pointers to derived classes constructor
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cmake_minimum_required(VERSION 3.25) | |
project(vectorOfPointers) | |
set(CMAKE_CXX_STANDARD 17) | |
add_executable(vectorOfPointers main.cpp) |
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#include <iostream> | |
#include <vector> | |
class Base { | |
public: | |
Base() = default; | |
virtual ~Base() = default; | |
virtual const char * object_name() = 0; | |
}; | |
class A : public Base { | |
public: | |
A() : Base() {std::cout << "Construct A" << std::endl;} | |
~A() override = default; | |
const char * object_name() override { | |
return "A"; | |
} | |
}; | |
class B : public Base { | |
public: | |
B() : Base() {std::cout << "Construct B" << std::endl;} | |
~B() override = default; | |
const char * object_name() override { | |
return "B"; | |
} | |
}; | |
// https://stackoverflow.com/a/44192185 | |
template<class T> Base* create() | |
{ | |
return new T; | |
} | |
int main() { | |
// SINGLE | |
Base* (*createMyClass)(void) = create<A>; | |
Base* myClass = createMyClass(); | |
// VECTOR OF FUNCTION POINTERS | |
std::vector<Base * (*)()> functions; | |
functions.push_back(create<A>); | |
functions.push_back(create<B>); | |
for (auto c : functions) { | |
Base * obj = c(); | |
std::cout << "Object name: " << obj->object_name() << std::endl; | |
delete obj; | |
} | |
// ARRAY OF FUNCTION POINTERS | |
Base * (*createPage[2]) (); | |
createPage[0] = create<A>; | |
createPage[1] = create<B>; | |
for (int i=0; i<2; i++) { | |
Base * obj = createPage[i](); | |
std::cout << "i: " << i << " Object name: " << obj->object_name() << std::endl; | |
delete obj; | |
} | |
return 0; | |
} |
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