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copied!<p>You really want to call a member function without using <code>.</code> or <code>-></code>? Really, <strong>really</strong>? Well, okay...</p> <p>Evil.h:</p> <pre><code>#ifdef __cplusplus extern "C" { #endif struct MyStruct { #ifdef __cplusplus MyStruct(); void method(int); #endif }; #ifdef __cplusplus } #endif </code></pre> <p>Evil.cc:</p> <pre><code>#include <iostream> #include "evil.h" MyStruct::MyStruct() { std::cout << "This is MyStruct's constructor" << std::endl; } void MyStruct::method(int i) { std::cout << "You passed " << i << std::endl; } </code></pre> <p>Evil.c:</p> <pre><code>#include "evil.h" int main() { struct MyStruct my_struct; _ZN8MyStructC1Ev(&my_struct); /* MyStruct::MyStruct() */ _ZN8MyStruct6methodEi(&my_struct, 3); /* MyStruct::method(int) */ return 0; } </code></pre> <p>This happens to work for my combination of gcc and g++ on Linux, but needless to say it relies on the platform ABI, and violates the C89 standard in calling functions of the form <em>underscore-capital letter</em>. It almost certainly won't work with virtual functions, and I'm not inclined to try. It may also be the most evil thing I've ever written. But still...</p> <hr> <p>EDIT: To quote the OP:</p> <blockquote> <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> </blockquote> <p>While it's true that every compiler since CFront has done it this way, that's just an implementation detail. The C++ standard is at pains <strong>not</strong> to specify how member functions should implemented, just how they should behave.</p> <p>Because it's an implementation detail, different platforms do it in different ways. This goes beyond just name mangling. For example, the calling convention used on Linux specifies that <code>this</code> is passed as the first argument; other implementations (Borland, IIRC?) pass <code>this</code> as the <em>last</em> argument.</p> <p>So, if you want to treat member functions as ordinary functions with an extra <code>this</code>, then you have to restrict yourself to a particular ABI. This post serves an example of how you might do that (or rather, an example of why you really shouldn't do that!)</p> <blockquote> <p>so, is there a way (or hack) to call D::foo with class object passed to it as function argument instead of using . or -> or .* or ->* operators on class object?</p> </blockquote> <p>A platform-specific, disgusting dirty hack...</p>

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