#include <iostream>
    #include <functional>
 
    using namespace std;
 
    class DoInDtor
    {
    public:
        typedef function<void()> F;
        DoInDtor(F f) : f_(f) {};
        ~DoInDtor() { f_(); }
    private:
        F f_;
    };
 
    void foo()
    {
        for(;;)
        {
            DoInDtor byeSayerCustom([](){ cout << "bye\n"; });
            auto cond = true; // could of course also be false sometimes
            if (cond)
                break;
        }
        // ...
        return;
    }
 
    int main()
    {
        foo();
    }

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