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POWrap STL vector and change behavior of its iterator
 

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    <p>There is such code:</p> <pre><code>#include &lt;iostream&gt; #include &lt;vector&gt; template &lt;class T&gt; class A{ public: class iterator : public std::vector&lt;T&gt;::iterator{ public: T&amp; operator*(){ ?? } }; iterator begin(){ return v.begin(); // error } iterator end(){ return v.end(); // error } void add(const T&amp; elem){ v.push_back(elem); } private: std::vector&lt;T&gt; v; }; int main() { A&lt;int&gt; a; a.add(2); a.add(4); for(A&lt;int&gt;::iterator it = a.begin(); it != a.end(); ++it){ std::cout &lt;&lt; *it &lt;&lt; std::endl; } return 0; } </code></pre> <p>This is a wrapper for <code>std::vector</code> with my own additional functions. I would like to use <code>std::vector</code>'s iterator, however I want only to change behavior of <code>operator*</code> for iterator:</p> <pre><code>T&amp; operator*(){ // do some additional function // normal behavior, return value of some element in vector ?? } </code></pre> <p>How can I use <code>std::vector</code> and its iterator with modification of only <code>operator*</code>? I would like also to wrap functions like <code>begin()</code> and <code>end()</code> for iterator, how to wrap them properly?</p> <p>EDIT:</p> <p>Using tips from answers in this topic, I managed to solve my problem in following way:</p> <pre><code>#include &lt;iostream&gt; #include &lt;vector&gt; template &lt;class T&gt; class A { public: class iterator : public std::vector&lt;T&gt;::iterator { public: iterator(typename std::vector&lt;T&gt;::iterator c) : std::vector&lt;T&gt;::iterator(c) { } T&amp; operator*() { std::cout &lt;&lt; "Im overloaded operator*\n"; return std::vector&lt;T&gt;::iterator::operator *(); } }; iterator begin() { return iterator(v.begin()); } iterator end() { return iterator(v.end()); } void add(const T&amp; elem) { v.push_back(elem); } private: std::vector&lt;T&gt; v; }; int main() { A&lt;int&gt; a; a.add(2); a.add(4); for (A&lt;int&gt;::iterator it = a.begin(); it != a.end() ; ++it) { std::cout &lt;&lt; *it &lt;&lt; std::endl; } return 0; } </code></pre> <p>Maybe it will be helpful for someone.</p>
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