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copied!<p>Ask your self first, how you would de-reference a void pointer? </p> <pre><code>void *p = /*something*/ ; cout << *p << endl; </code></pre> <p>The above code is meaningless, one of the reasons we have void is so we can say "I need to do some generic pointer work here, and I neither know nor care what I'm pointing to". By definition, the compiler doesn't know what a void * points to, therefore it can't dereference it. You can - by casting - but the compiler can't.</p> <p>A reference to a void sufferes from the same problem, by definition the data pointed to doesn't have a type, therefore it can't be referenced in any meaningful way.</p> <p>To reference it you - the programmer - need to cast it to another type, then you can have a typed reference to it.</p> <p>Not sure if I explained this as well as I wanted to.</p> <p>Ruben, any thoughts?</p> <p><strong>EDIT:</strong> To answer your edit.</p> <p>Take the first function, where you pass void* data. data is a perfectly valid item, you can compute with it, or if you've some logging implemented, you can log it.</p> <pre><code>logger << data; </code></pre> <p>and you'll get the address data points to. If you try to dereference data, the compiler will give you an error (don't have C++ compiler handy at moment, so not sure of the actual error). e.g. </p> <pre><code>void* data = /* some assignment */; logger << *data; // compiler error. </code></pre> <p>Now, the compiler won't let you dereference a void* for any reason (it doesn't make sense), the same stands for a reference to void &data, except that because it's a reference <em>it's implicitly dereferenced all the time</em>. The compiler won't let you dereference a void* on one operation, it's not going to let you dereference it constantly.</p> <pre><code>void& data = /* some assignment *.; logger << data; // means same as logger << *data above </code></pre> <p>You can't do <strong>ANYTHING</strong> to data <strong>EXCEPT</strong> take it's address, and there's a perfectly good - and safe - method built into the languge to do that, i.e.</p> <pre><code>void* data; </code></pre> <p>Is this making any more sense?</p>

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