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POIs there a way to call member function without .* or ->* operator
 

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    <p>Below method of calling <code>D::foo</code> function via pointer-to-member function will generate error: <strong>must use <code>.*</code> or <code>-&gt;*</code> to call pointer-to-member function in 'f (...)'</strong> .. of course that is not how we call pointer-to-member functions.</p> <p>The correct way of calling is <code>(d.*f)(5);</code> OR <code>(p-&gt;*f)(5);</code></p> <p>My question is, 'Is there a way to call member function of a class without the class object on left hand side? I wonder if we could pass class object (<code>this</code>) as regular argument?</p> <p>In my mind, at end of the day (at assembly/binary level) all member functions of a class are normal functions which should operate on n + 1 arguments where (+1 is for <code>this</code>) </p> <p>If we talk about <code>D::foo</code> function below, at assembly/binary level it should operate on two arguments:</p> <ol> <li>The class object itself (pointer to class D object called <code>this</code>) </li> <li>and the <code>int</code>.</li> </ol> <p>so, is there a way (or hack) to call <code>D::foo</code> with class object passed to it as function argument instead of using <code>. or -&gt; or .* or -&gt;*</code> operators on class object?</p> <p><strong>Sample Code:</strong></p> <pre><code>#include &lt;iostream&gt; using namespace std; class D { public: void foo ( int a ) { cout &lt;&lt; "D" &lt;&lt; endl; } int data; }; //typedef void __cdecl ( D::* Func)(int); typedef void ( D::* Func)(int); int main ( void ) { D d; Func f = &amp;D::foo; f(&amp;d, 5); return 1; } </code></pre> <p>One method is using boost bind i.e</p> <pre><code>(boost:: bind (&amp;D::foo, &amp;d, 5)) (); </code></pre> <p>EDIT: "Please note I am not looking for a version of this program which works, I know how to make it work"</p>
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    1. USMike
    1. USVishnu Kanwar
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    1. COLook at the answer of this [question](http://stackoverflow.com/questions/112738/how-does-boost-bind-work-behind-the-scenes-in-general)
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    2. COThere's no "magic". Somewhere in the `bind` result type's `operator()` will be something like `(ptr->*fun)(arg)`; you just don't see it because it's buried in the library implementation.
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      1. USMike Seymour
    3. COIt's not an "artificial restriction" any more than requiring a `;` after a statement is an "artificial restriction." It's just the syntax of the language.
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