3rdParty/boost/1.78.0/libs/mpl/doc/src/refmanual/BidirectionalSequence.rst
.. Sequences/Concepts//Bidirectional Sequence |20
A |Bidirectional Sequence| is a |Forward Sequence| whose iterators model |Bidirectional Iterator|.
|Forward Sequence|
In addition to the requirements defined in |Forward Sequence|,
for any |Bidirectional Sequence| s the following must be met:
+---------------------------+-----------------------------------+---------------------------+
| Expression | Type | Complexity |
+===========================+===================================+===========================+
| begin<s>::type | |Bidirectional Iterator| | Amortized constant time |
+---------------------------+-----------------------------------+---------------------------+
| end<s>::type | |Bidirectional Iterator| | Amortized constant time |
+---------------------------+-----------------------------------+---------------------------+
| back<s>::type | Any type | Amortized constant time |
+---------------------------+-----------------------------------+---------------------------+
|Semantics disclaimer...| |Forward Sequence|.
+---------------------------+-----------------------------------------------------------------------+
| Expression | Semantics |
+===========================+=======================================================================+
| back<s>::type | The last element in the sequence; see |back|. |
+---------------------------+-----------------------------------------------------------------------+
|Sequences|, |Forward Sequence|, |Random Access Sequence|, |Bidirectional Iterator|, |begin| / |end|, |back|
.. 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)