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    <p>First make generic monitor class. With power of C++11 you can do it as simple as this:</p> <pre><code>template &lt;class F&gt; struct FunctionType; template &lt;class R, class Object, class... Args&gt; struct FunctionType&lt;R (Object::*)(Args...)&gt; { typedef R return_type; }; template &lt;class R, class Object, class... Args&gt; struct FunctionType&lt;R (Object::*)(Args...) const&gt; { typedef R return_type; }; template &lt;class Object_&gt; class Monitor { public: typedef Object_ object_type; template &lt;class F, class... Args &gt; typename FunctionType&lt;F&gt;::return_type operation(const F&amp; f, Args... args) { critical_section cs; return (object.*f)(args...); } template &lt;class F, class... Args &gt; typename FunctionType&lt;F&gt;::return_type operation(const F&amp; f, Args... args) const { critical_section cs; return (object.*f)(args...); } private: object_type object; class critical_section {}; }; </code></pre> <p>Of course <code>critical_section</code> implementation is up to you. I recommend POSIX or some BOOST.</p> <p>It is ready to use right now:</p> <pre><code>Monitor&lt;std::vector&lt;int&gt; &gt; v; v.operation((void (std::vector&lt;int&gt;::*)(const int&amp;)) &amp;std::vector&lt;int&gt;::push_back, 1); v.operation((void (std::vector&lt;int&gt;::*)(const int&amp;)) &amp;std::vector&lt;int&gt;::push_back, 2); size = v.operation(&amp;std::vector&lt;int&gt;::size); std::cout &lt;&lt; size &lt;&lt; std::endl; </code></pre> <p>As you can see sometimes you'll need to explicitly state which member function you want to call - std::vector&lt;> has more than one push_back... </p> <hr> <p>For compilers which still do not support variadic template - the solution without it below - I have time for up to two arguments - it is very inconvenient - if required - add function with more arguments:</p> <pre><code>template &lt;class F&gt; struct FunctionType; template &lt;class R, class Object&gt; struct FunctionType&lt;R (Object::*)()&gt; { typedef R return_type; }; template &lt;class R, class Object&gt; struct FunctionType&lt;R (Object::*)() const&gt; { typedef R return_type; }; template &lt;class R, class Object, class Arg1&gt; struct FunctionType&lt;R (Object::*)(Arg1)&gt; { typedef R return_type; }; template &lt;class R, class Object, class Arg1&gt; struct FunctionType&lt;R (Object::*)(Arg1) const&gt; { typedef R return_type; }; template &lt;class R, class Object, class Arg1, class Arg2&gt; struct FunctionType&lt;R (Object::*)(Arg1,Arg2)&gt; { typedef R return_type; }; template &lt;class R, class Object, class Arg1, class Arg2&gt; struct FunctionType&lt;R (Object::*)(Arg1,Arg2) const&gt; { typedef R return_type; }; template &lt;class Object_&gt; class Monitor { public: typedef Object_ object_type; template &lt;class F&gt; typename FunctionType&lt;F&gt;::return_type operation(const F&amp; f) { critical_section cs; return (object.*f)(); } template &lt;class F&gt; typename FunctionType&lt;F&gt;::return_type operation(const F&amp; f) const { critical_section cs; return (object.*f)(); } template &lt;class F, class Arg1&gt; typename FunctionType&lt;F&gt;::return_type operation(const F&amp; f, Arg1 arg1) { critical_section cs; return (object.*f)(arg1); } template &lt;class F, class Arg1&gt; typename FunctionType&lt;F&gt;::return_type operation(const F&amp; f, Arg1 arg1) const { critical_section cs; return (object.*f)(arg1); } template &lt;class F, class Arg1, class Arg2&gt; typename FunctionType&lt;F&gt;::return_type operation(const F&amp; f, Arg1 arg1, Arg2 arg2) { critical_section cs; return (object.*f)(arg1, arg2); } template &lt;class F, class Arg1, class Arg2&gt; typename FunctionType&lt;F&gt;::return_type operation(const F&amp; f, Arg1 arg1, Arg2 arg2) const { critical_section cs; return (object.*f)(arg1, arg2); } private: object_type object; class critical_section {}; }; </code></pre>
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    1. POMaking a C++ class a Monitor (in the concurrent sense)
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    1. COThis is a very elegant solution; the only downside is that it requires variadic templates support, which VC++ still lacks.
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    2. CO@dario_ramos Once upon a time C++ had no variadic templates ;) You can use overridden methods: `operation` with 0,1,2,3... arguments instead of just one `operation` with any number of arguments. Assuming noone uses more than 10 arguments it is possible to implement - however more troublesome than variadic templates...
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    3. COThat's a very neat solution. I don't suppose you can recommend a book or article that could explain the use of the variadic templates a bit more? I find the struct FunctionType<R (Object::*)(Args...)> hard to fathom (particularly the Object::* bit.)
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