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copied!<p>You are right, it is a scooping issue. In the <code>inherit</code> constructor, <code>funcA</code> and <code>funcB</code> are both allocated on the stack and destroyed once the function goes out of scope. The leaves <code>m_map</code> with stale pointers.</p> <p>What you really want is something like</p> <pre><code>inherit::inherit(int lenght, int width, int height) :base(length, width) { m_height = height; // allocated on the heap TSpecificFunctor<inherit> * funcA = new TSpecificFunctor<inherit>(this, &inherit::volume); m_map["a"] = funcA; // allocated on the heap TSpecificFunctor<inherit> * funcB = new TSpecificFunctor<inherit>(this, &inherit::area2); m_map["b"] = funcB; } // when this function exits funcA and funcB are not destroyed </code></pre> <p>But, to avoid any memory leaks, the destructor for <code>inherit</code> will need to clean up the values</p> <pre><code>inherit::~inherit() { for(TestMap::iterator it = m_map.begin(); it != m_map.end(); ++it) { delete it->second; } } </code></pre> <p>Using <code>new</code> and <code>delete</code> can easily lead to memory leaks. To prevent them, I would suggest looking into smart points like <code>std::unique_ptr</code> and <code>std::shared_ptr</code>. Also, functors are becoming obsolete with the introduction of lambdas in C++11. They are really neat and worth looking into if you are not familiar with them.</p> <hr> <p>If your compiler supports them, to do this with lambdas</p> <pre><code>#include <functional> // ... typedef std::map<std::string, std::function<int(void)>> TestMap; // ... inherit::inherit(int length, int width, int height):base(length, width) { m_height = height; m_map["a"] = [this]() -> int { return volume(); }; m_map["b"] = [this]() -> int { return area2(); }; // can be called like so m_map["a"](); m_map["b"](); } // No need to clean up in destructors </code></pre>

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