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    <p>Here is an approach based on making a <code>std::multimap</code> from the <code>std::type_index</code> of the function to a <code>std::function</code> of the appropriate type:</p> <pre><code>#include &lt;functional&gt; #include &lt;iostream&gt; #include &lt;map&gt; #include &lt;memory&gt; #include &lt;typeindex&gt; void freestanding() { std::cout &lt;&lt; "freestanding" &lt;&lt; std::endl; } void freestandingInt(int iArg) { std::cout &lt;&lt; "freestandingInt " &lt;&lt; iArg &lt;&lt; std::endl; } // Base class for all functions so that we can store all functions // in a single container. struct Function { virtual ~Function() { } }; // Derived class template for functions with a particular signature. template &lt;typename T&gt; struct BasicFunction : Function { std::function&lt;T&gt; function; BasicFunction(std::function&lt;T&gt; function) : function(function) { } }; // Generic container of listeners for any type of function typedef std::multimap&lt;std::type_index,std::unique_ptr&lt;Function&gt; &gt; Listeners; template &lt;typename Func&gt; static void addListener(Listeners &amp;listeners,Func &amp;function) { std::type_index index(typeid(Func)); std::unique_ptr&lt;Function&gt; func_ptr(new BasicFunction&lt;Func&gt;(std::function&lt;Func&gt;(function))); listeners.insert(Listeners::value_type(index,std::move(func_ptr))); } template &lt;typename... Args&gt; static void callListeners(const Listeners &amp;listeners,Args&amp;&amp;... args) { typedef void Func(typename std::remove_reference&lt;Args&gt;::type...); std::type_index index(typeid(Func)); Listeners::const_iterator i = listeners.lower_bound(index); Listeners::const_iterator j = listeners.upper_bound(index); for (;i!=j; ++i) { const Function &amp;f = *i-&gt;second; std::function&lt;Func&gt; func = static_cast&lt;const BasicFunction&lt;Func&gt; &amp;&gt;(f).function; func(std::forward&lt;Args&gt;(args)...); } } struct Dispatcher { typedef struct Event_ { Listeners listeners; } Event; template&lt;class... Args&gt; void dispatch(int eventNr, Args&amp;&amp;... args) { callListeners(events[eventNr].listeners,std::forward&lt;Args&gt;(args)...); } std::map&lt;int, Event&gt; events; }; int main (int argc, char **argv) { Dispatcher disp; addListener(disp.events[0].listeners,freestanding); addListener(disp.events[0].listeners,freestandingInt); disp.dispatch(0,5); } </code></pre> <p>Output:</p> <pre><code>freestandingInt 5 </code></pre>
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    1. POCollection of std::functions with different arguments
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    1. USVaughn Cato
    1. USVaughn Cato
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    1. POCollection of std::functions with different arguments
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    1. COI've used it, and I really like it. It's also a very good example of the use of multimap with type_index, thanks
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      1. USAlex Darsonik
 

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