Standard C++ Library
Copyright 1998, Rogue Wave Software, Inc.
- A forward-moving iterator that can both read and write.
For a complete discussion of iterators, see the Iterators
section of this reference.
Iterators are a generalization of pointers that allow a C++
program to uniformly interact with different data struc-
tures. Forward iterators are forward moving, and have the
ability to both read and write data. These iterators satisfy
the requirements listed below.
KEY TO ITERATOR REQUIREMENTS
The following key pertains to the iterator requirements
a and b values of type X
n value representing a distance between two iterators
u, Distance, tmp and m identifiers
r value of type X&
t value of type T
REQUIREMENTS FOR FORWARD ITERATORS
The following expressions must be valid for forward itera-
X u u might have a singular value
X() X() might be singular
X(a) copy constructor, a == X(a)
X u(a) copy constructor, u == a
X u = a assignment, u == a
a == b, a != b return value convertible to bool
*a return value convertible to T&
a->m equivalent to (*a).m
++r returns X&
r++ return value convertible to const X&
*r++ returns T&
Forward iterators have the condition that a == b implies *a
There are no restrictions on the number of passes an
algorithm may make through the structure.