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copied!<p>Please have a look at differences between pointers and references - while the standard leaves it open how references are implemented, they are at the moment always implemented as pointers.</p> <p>Which means that the main difference between them is a) semantics b) pointers can be reseated c) pointers can be null.</p> <p>So the short answer is, this was done on purpose. When you as programmer see a reference you should know that a) that reference is populated b) it won't change (and c) you can use it with the same semantics as an object).</p> <p>Would the standard allow a null reference, you would always have to check for null before using a reference, which was not wanted.</p> <p>Edit:</p> <p>Regarding your edit, I guess the confusion here might stem from the fact that most simpler OO languages hide what is going on. To take Java as example, while it looks like you have NULL objects, and can assign them, you really can't - what is really going on is that Java only has pointers, and can assign null values to those pointers. Since it is impossible to actually have objects directly in Java, they do away with pointer semantics and treat the pointer as the object. C++ is simply more powerful - and error prone (Java enthusiast would say that stack user class instances are not required, and the decision to not have them in Java was driven to reduce complexity, and make Java easier to use). It also follows that, since Java doesn't have objects, it doesn't have references. What really doesn't help, though, is that Java calls what a C++ person would call a pass-by-value of a pointer a pass-by-reference.</p>

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