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For those who don't know what typename does or why it's in the language (or haven't heard of it), I'll provide a quick overview. If you know, skip ahead four paragraphs template void foo() { vector::iterator * x; ... } The line I'll be talking about is the one that looks like it should be a declaration. It's pretty clear that the programmer intends this to be a declaration of a variable called x whose type is a pointer to an iterator object, where iterator is found in the scope vector. However, the compiler is (depending how you look at it) either stupider or smarter than the programmer: it knows that there could be a specialization of the vector template for whatever T is finally used where iterator is a static variable. And who knows, maybe there's a global x somewhere. In that case, that line is a expression that multiplies the class static variable called iterator with the global variable x. The problem arises anytime you have what's called a dependent qualified type. The "dependent" part (in the context of C++) means that it depends on a template parameter. For instance, T, T::iterator, and vector are all dependent names. The "qualified" part means that it's not just an undecorated name; it has a "::" in it. (See below for complications on this rule.) Any time (almost...) there is a dependent qualified name, C++ requires you to use typename. So the line above should be changed to "typename vector::iterator * x" [RESUMING] So the presence of typename is an unfortunate consequence of the syntax/semantics of templates. However, even given that it's here, it's WAY WAY too complicated. Here is what I think the C++ committee should have chosen for the rules for typename: 1. before dependent qualified types, typename is required 2. before other types, typename is optional I can think of no parsing or other problems this would create. I posted a query about this to comp.lang.c++ and comp.lang.c++.moderated a bit ago and received no response, so I'm not sure of it; so if you can come up with something I'd be glad to hear it. But here are the ACTUAL typename rules: 1. Before unqualified types (dependent or not), typename is prohibited. 2. Outside of a template declaration, typename is prohibited. 3. Inside a template declaration, typename is optional before qualified but nondependent names. (E.g. both 'typename vector::iterator' and just 'vector::iterator' are legal.) However, it should probably be noted that an explicit specialization of a template is NOT itself a template, and so use of typename falls under rule 2, not this one. 4. Before a qualified dependent type, typename is required, except that when naming a base class in the base-specifier or a type in a constructor initializer list, typename is prohibited. 5. The requirement to use typename is transitive. For instance, if you do 'typedef typename T::iterator T_iterator', you still have to say 'typename T_iterator'. I can think of no reason for this rule. WAY WAY WAY too complicated, especially the addendum to rule 3, the exceptions in rule 4, and the entire rule 5.