.. Iterators/Iterator Metafunctions//next |30

next

Synopsis

.. parsed-literal::

template<
      typename Iterator
    >
struct next
{
    typedef |unspecified| type;
};

Description

Returns the next iterator in the sequence. |Note:| next has a number of overloaded meanings, depending on the type of its argument. For instance, if X is an |Integral Constant|, next<X> returns an incremented |Integral Constant| of the same type. The following specification is iterator-specific. Please refer to the corresponding concept's documentation for the details of the alternative semantics |-- end note|.

Header

.. parsed-literal::

#include <boost/mpl/next_prior.hpp>

Parameters

+---------------+---------------------------+-----------------------------------+ | Parameter | Requirement | Description | +===============+===========================+===================================+ | Iterator | |Forward Iterator|. | An iterator to increment. | +---------------+---------------------------+-----------------------------------+

Expression semantics

For any |Forward Iterator|\ s iter:

.. parsed-literal::

typedef next<iter>::type j; 

:Return type: |Forward Iterator|.

:Precondition: iter is incrementable.

:Semantics: j is an iterator pointing to the next element in the sequence, or is past-the-end. If iter is a user-defined iterator, the library-provided default implementation is equivalent to

.. parsed-literal::

    typedef iter::next j;

Complexity

Amortized constant time.

Example

.. parsed-literal::

typedef vector_c<int,1> v;
typedef begin<v>::type first;
typedef end<v>::type last;

BOOST_MPL_ASSERT(( is_same< next<first>::type, last > ));

See also

|Iterators|, |begin| / |end|, |prior|, |deref|

.. copyright:: Copyright 2001-2009 Aleksey Gurtovoy and David Abrahams Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)