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copied!<p>You need a pointer-to-function:</p> <pre><code>void* (*OnJoinFn)(char*, char*); </code></pre> <p>In your <code>Irc</code> class,</p> <pre><code>class Irc { public: OnJoinFn onJoin; }; </code></pre> <p>This can be assigned as you are doing above:</p> <pre><code>int main() { Irc irc(stuff); irc.onJoin = join; } </code></pre> <p>But I wonder, if you are just learning C++, do you really need a pointer-to-function? pointers-to-function are certianly legal and valid, but an unusual entity and I would typically expect to use some other mechanism. As a start, I would suggest looking in to abstract base classes:</p> <pre><code>class IIrc { public: virtual void* OnJoin(const char*, const char*) = 0; // pure virtual virtual ~IIrc() {}; // Don't forget to implement a virtual destructor in any ABC }; class MyIrc : public IIrc { public: void* OnJoin(const char* sender, const char* channel*) { // YOUR CODE HERE } }; int main() { IIrc* irc = new MyIrc; irc->OnJoin (...); } </code></pre> <p>I've taken the liberty of introducing const correctness in <code>OnJoin</code>.</p> <p>You should also consider not returning a <code>void*</code>, which bypasses most of C++'s type safety mechanisms, but a pointer to an actual object, or another interface.</p> <p>Finally, using <code>new</code> (and <code>delete</code>, which is missing here, resulting in a memory leak) is poor practice. Instead, prefer to allocate things on the stack or, if you really need dynamic allocation, use a smart pointer.</p>

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