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    <p>If the function is not <code>static</code>, you cannot pass it in input to a function that accepts a non-member function pointer. </p> <p>Consider that a non-<code>static</code> member function has an implicit pointer to <code>ClassName</code> as its first parameter, which points to the object on which the member function is being invoked.</p> <pre><code>struct X { static void foo() { } // Does not have an implicit "this" pointer argument void bar() { } // Has an implicit "this" pointer argument }; int main() { void (*f)() = &amp;X::foo; // OK: foo is static void (*g)() = &amp;X::bar; // ERROR! bar is non-static } </code></pre> <p>Here, not even <code>std::bind()</code> will work, because the result is not convertible to a function pointer. Lambdas are convertible to function pointers, but only if they are non-capturing (and a lambda here would need to capture the object to invoke the member function on).</p> <p>Therefore, the only (ugly) workaround is to have a global adapter function which invokes the member function on an object which is available through a global pointer variable. The global pointer variable is set prior to calling the function:</p> <pre><code>struct X { void bar() { } }; void function_taking_a_function_pointer(void (*f)()) { // Do something... f(); } X* pX = nullptr; void bar_adapter() { pX-&gt;bar(); } int main() { X x; // Some object I want to invoke the member function bar() on... pX = &amp;x; // Set the global pointer and invoke the function... function_taking_a_function_pointer(bar_adapter); } </code></pre> <p>If you want, you can make this slightly more flexible by turning <code>bar_adapter</code> into a function <em>template</em>, and passing the pointer-to-member-function as a template argument:</p> <pre><code>template&lt;typename T, void (T::*mf)()&gt; void adapter() { (pX-&gt;*mf)(); } </code></pre> <p>Here is how you would use it:</p> <pre><code>#include &lt;iostream&gt; struct X { void foo() { std::cout &lt;&lt; "X::foo()" &lt;&lt; std::endl; } void bar() { std::cout &lt;&lt; "X::bar()" &lt;&lt; std::endl; } }; void function_taking_a_function_pointer(void (*f)()) { // Do something... f(); } X* pX = nullptr; template&lt;typename T, void (T::*mf)()&gt; void adapter() { (pX-&gt;*mf)(); } int main() { X x; // Some object I want to invoke the member function bar() on... pX = &amp;x; // Set the global pointer and invoke the function(s)... function_taking_a_function_pointer(adapter&lt;X, &amp;X::foo&gt;); function_taking_a_function_pointer(adapter&lt;X, &amp;X::bar&gt;); } </code></pre> <p>Finally, here is a <a href="http://liveworkspace.org/code/41HfPq%2438" rel="nofollow">live example</a>.</p>
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    1. USAndy Prowl
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    1. COthank you, very informative answer.
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    2. CO@FlyingSwissman: Glad I could help
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