iterator Struct
An empty base struct used to ensure that a user-defined iterator class works properly with iterator_trait
s.
Syntax
struct iterator {
typedef Category iterator_category;
typedef Type value_type;
typedef Distance difference_type;
typedef Distance distance_type;
typedef Pointer pointer;
typedef Reference reference;
};
Remarks
The template struct serves as a base type for all iterators. It defines the member types
iterator_category
(a synonym for the template parameterCategory
).value_type
(a synonym for the template parameterType
).difference_type
(a synonym for the template parameterDistance
).distance_type
(a synonym for the template parameterDistance
)pointer
(a synonym for the template parameterPointer
).reference
(a synonym for the template parameterReference
).
Note that value_type
should not be a constant type even if pointer
points at an object of const
Type
and reference designates an object of const
Type
.
Example
See iterator_traits for an example of how to declare and use the types in the iterator base class.
Requirements
Header: <iterator>
Namespace: std
See also
<iterator>
Thread Safety in the C++ Standard Library
C++ Standard Library Reference