iterator_traits

iterator_traits

template <class Iterator> class iterator_traits;
template <class T> class iterator_traits<T*>;
template <class T> class iterator_traits<const T*>;

Iterator의 특성을 나타내는 Traits(특성) Class

Standard Algorithm은 iterator_traits 인스턴스화의 Member를 이용하여 전달된 Iterator의 속성과 범위를 결정한다.

모든 Iterator type에 대해서 iterator_traits 클래스의 템플릿은 최소한 다음 멤버 유형이 정의되어야 한다.

member	description
difference_type	Type to express the result of subtracting one iterator from another.
value_type	The type of the element the iterator can point to
pointer	The type of a pointer to an element the iterator can point to.
reference	The type of a reference to an element the iterator can point to
iterator_category	The iterator category.

iterator category

• input_iterator_tag
• output_iterator_tag
• forward_iterator_tag
• bidirectional_iterator_tag
• random_access_iterator_tag