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    <pre><code>#include &lt;iostream&gt; void MyFunction(float a){std::cout &lt;&lt; "float\n";} void MyFunction(int a){std::cout &lt;&lt; "int\n";} template&lt;typename Func, typename T&gt; void Do( Func f, T t ) { f(t); } template&lt;typename T&gt; void DoMyFunction( T t ) { Do(static_cast&lt;void(*)(T)&gt;(MyFunction), t); } template&lt;typename T&gt; void DoSomeFunction( T t, void(*func)(T) ) { Do(func, t); } int main() { float a; MyFunction(a); void (*manualFunctionPointer)(float) = MyFunction; manualFunctionPointer(a); // Do(MyFunction, a); -- does not compile Do(static_cast&lt;void(*)(float)&gt;(MyFunction), a); DoMyFunction(a); DoSomeFunction(a, MyFunction); } </code></pre> <p>The above works. I picked a MyFunction in 4 different ways.</p> <p>If you are willing to do some boilerlate, and want to solve the "what if a is a <code>char</code>" problem, then this might help:</p> <pre><code>// wrap the idea of calling MyFunction in a type: struct MyFunctionFunctor { template&lt;typename T&gt; static auto Do( T&amp;&amp; t )-&gt;decltype(MyFunction(std::forward(t))) { return MyFunction(std::forward(t)); } }; // Calling MyFunctionFunctor::Do( x ) will basically do static dispatch on all of // the overloads of MyFunction // wrap the idea of dispatching a variable to a functor: template&lt;typename T, typename Functor&gt; struct Dispatch { static auto Do( T t )-&gt;decltype( Functor::Do( t ) ) { return Functor::Do( t ); } } int main() { char a; auto func_ptr = &amp;Dispatch&lt;decltype(a), MyFunctionFunctor&gt;::Do; func_ptr(a); } </code></pre> <p>but, as noted, this requires we wrap our <code>MyFunction</code> up so that it is described by a type. I'm not aware of a way to do this without boilerplate.</p>
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    1. POHow to get a function pointer to the overloaded function that the compiler chooses?
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    1. USYakk - Adam Nevraumont
    1. USYakk - Adam Nevraumont
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    1. COthere I still have to know "float" is the type of 'a' though. John Bandela's void (*manualFunctionPointer)(decltype(a)); is what I was looking for :)
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      1. USDavid Doria
    2. CONow try with `char a;`. This solution does not work.
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    3. COIf you want that, you might have to iterate over every type a can be implicitly promoted to. For non user defined conversions this is theoretically possible, then use an insane SFINAE on the list of types to find the first one that works with your function pointer. It probably is not worth it. I cannot figure out how to do this with user defined conversions without lots of help from the cost of the conversion. If we had constexpr function pointers I could do this with a template class static method wrapper. Or if the func was a functor which I could call by type.
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      1. USYakk - Adam Nevraumont
 

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