Transaction

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#include <exception>
#include <iostream>
#include <vector>
#include <boost/shared_ptr.hpp>

class transaction
{
public:

    transaction()
    : incomplete(true)
    {
    }

    ~transaction()
    {
        if(incomplete)
        {
            revert();
        }
    }

    template <class T>
    void begin(T& t)
    {
        params.push_back(param_ptr(new param_impl<T>(t)));
    };

    void commit()
    {
        incomplete = false;
    }

private:

    class param
    {
    public:

        virtual ~param() {};
        virtual void revert() const = 0;
    };

    template <class T>
    class param_impl : public param
    {
    public:

        param_impl(T& t)
        : reference(t)
        , original (t)
        {
        }

        virtual void revert() const
        {
            reference = original;
        }

    private:

        T& reference;
        T  original;
    };

    typedef boost::shared_ptr<param> param_ptr;

    typedef std::vector<param_ptr> param_container;

    bool incomplete;
    param_container params;

    void revert()
    {
        for
        (
            param_container::const_reverse_iterator i = params.rbegin();
            i != params.rend();
            ++i
        )
        {
            (*i)->revert();
        }
    }
};

int main()
{
    std::string name = "Angelina";
    float bosom  = 85.3f;
    float waist  = 68.5f;
    float pelvis = 88.8f;

    try
    {
        transaction trn;
        trn.begin(name);
        trn.begin(bosom);
        trn.begin(waist);
        trn.begin(pelvis);

        name   = "Olga";
        bosom  = 102.4f;
        waist  = 59.3f;
        pelvis = 92.3f;

        // ...
        // Здесь что-то происходит
        // ...

        throw std::runtime_error("Wife is coming!");

        trn.commit();
    }
    catch(std::exception const&)
    {
        std::cout << "Hi, dear!" << std::endl;
    }

    return 0;
}