constructing object on first use as return value of (pointer to) object-returning function , C++ (gcc)

constructing object on first use as return value of (pointer to) object-returning function

//see also: https://rextester.com/CTC97213
//constructing object on first use as return value of (pointer to) object-returning function 
// no need for the "application()->close()" anymore...
//g++  5.4.0
//Coded by Twareintor (2020)
#include <iostream>
#include <memory>

class CxxApplication
{
    friend CxxApplication* application();
    static std::unique_ptr<CxxApplication> inst;
public:
    CxxApplication(){std::cout<<"app opened\n";}
    ~CxxApplication(){std::cout<<"app closed\n";}
    void perform(){std::cout<<"app performing ... done\n";}
    void perform(int i){std::cout<<"app performing ... "<< i <<" times\n";}
    // void close(){if(inst) delete inst;} // no more needed
};

std::unique_ptr<CxxApplication> CxxApplication::inst(nullptr);

CxxApplication* application()
{
    if(!CxxApplication::inst.get()) 
        CxxApplication::inst = std::unique_ptr<CxxApplication>(new CxxApplication());
    return CxxApplication::inst.get();
}

int main()
{
    application()->perform();
    application()->perform(30);
    // application()->close(); // no more needed
    return 0;
}


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