STL迭代器的实现问题。。
下面是从MSDN上截取的一段STL中Vector 的定义~
能帮我解释一下这些typedef定义的意思和他们是如何实现的么？
template<class T, class A = allocator<T> > class vector {public: typedef A allocator_type; typedef A::size_type size_type; typedef A::difference_type difference_type; typedef A::reference reference; typedef A::const_reference const_reference; typedef A::value_type value_type; typedef T0 iterator; typedef T1 const_iterator; typedef reverse_iterator<iterator, value_type, reference, A::pointer, difference_type> reverse_iterator;