Standard Template Library Programmer's Guide

A type that is a model of Forward Iterator may be either mutable or immutable , as defined in the Trivial Iterators requirements.

Input Iterator, Output Iterator

The same as for Input Iterator

XA type that is a model of Forward Iterator

TThe value type of X

i, j Object of type X

t Object of type T

Forward Iterator does not define any new expressions beyond those defined in Input Iterator. However, some of the restrictions described in Input Iterator are relaxed.

Forward Iterator does not define any new expressions beyond those defined in Input Iterator. However, some of the restrictions described in Input Iterator are relaxed.

The complexity of operations on Forward Iterators is guaranteed to be amortized constant time.

• T*

• hash_set::iterator

Notes

[1] The restrictions described in Input Iterator have been removed. Incrementing a forward iterator does not invalidate copies of the old value and it is guaranteed that, if i and j are dereferenceable and i == j , then ++i == ++j . As a consequence of these two facts, it is possible to pass through the same Forward Iterator twice.

Input Iterator, Output Iterator, Bidirectional Iterator, Random Access Iterator, Iterator overview

Category: iterators

Component type: concept

A Bidirectional Iterator is an iterator that can be both incremented and decremented. The requirement that a Bidirectional Iterator can be decremented is the only thing that distinguishes Bidirectional Iterators from Forward Iterators.

Forward Iterator

The same as for Forward Iterator.

XA type that is a model of Bidirectional Iterator

TThe value type of X

i, jObject of type X

tObject of type T

In addition to the expressions defined in Forward Iterator, the following expressions must be valid.

Semantics of an expression is defined only where it is not defined in Forward Iterator.

The complexity of operations on bidirectional iterators is guaranteed to be amortized constant time.

• T*

• list::iterator

Input Iterator, Output Iterator, Forward Iterator, Random Access Iterator, Iterator overview

Category: iterators

Component type: concept

A Random Access Iterator is an iterator that provides both increment and decrement (just like a Bidirectional Iterator), and that also provides constant-time methods for moving forward and backward in arbitrary-sized steps. Random Access Iterators provide essentially all of the operations of ordinary C pointer arithmetic.

Bidirectional Iterator, LessThan Comparable

The same as for Bidirectional Iterator

XA type that is a model of Random Access Iterator

TThe value type of X

DistanceThe distance type of X

i, jObject of type X

tObject of type T

nObject of type Distance

In addition to the expressions defined in Bidirectional Iterator, the following expressions must be valid.

Semantics of an expression is defined only where it differs from, or is not defined in, Bidirectional Iterator or LessThan Comparable.

All operations on Random Access Iterators are amortized constant time. [5]