Using types defined in template arguments

Answer 1

You're missing the required typename keyword:

typedef typename container::value_type elementtype;

This is because container is a dependent name in this template, so the compiler has no way of knowing whether container::value_type is always a type or not, as it may depend on the choice of container.

Surely this question is a FAQ somewhere?

Edit, it is: http://www.parashift.com/c++-faq-lite/templates.html#faq-35.18