| .. Sequences/Intrinsic Metafunctions//push_back |
| |
| push_back |
| ========= |
| |
| Synopsis |
| -------- |
| |
| .. parsed-literal:: |
| |
| template< |
| typename Sequence |
| , typename T |
| > |
| struct push_back |
| { |
| typedef |unspecified| type; |
| }; |
| |
| |
| |
| Description |
| ----------- |
| |
| ``push_back`` performs an insertion at the end of the sequence with guaranteed |O(1)| |
| complexity. |
| |
| Header |
| ------ |
| |
| .. parsed-literal:: |
| |
| #include <boost/mpl/push_back.hpp> |
| |
| |
| |
| Model of |
| -------- |
| |
| |Tag Dispatched Metafunction| |
| |
| |
| Parameters |
| ---------- |
| |
| +---------------+-------------------------------+-----------------------------------------------+ |
| | Parameter | Requirement | Description | |
| +===============+===============================+===============================================+ |
| | ``Sequence`` | |Back Extensible Sequence| | A sequence to insert into. | |
| +---------------+-------------------------------+-----------------------------------------------+ |
| | ``T`` | Any type | The element to be inserted. | |
| +---------------+-------------------------------+-----------------------------------------------+ |
| |
| |
| Expression semantics |
| -------------------- |
| |
| For any |Back Extensible Sequence| ``s`` and arbitrary type ``x``: |
| |
| |
| .. parsed-literal:: |
| |
| typedef push_back<s,x>::type r; |
| |
| :Return type: |
| |Back Extensible Sequence|. |
| |
| :Semantics: |
| Equivalent to |
| |
| .. parsed-literal:: |
| |
| typedef insert< s,end<s>::type,x >::type r; |
| |
| |
| :Postcondition: |
| ``back<r>::type`` is identical to ``x``; |
| |
| .. parsed-literal:: |
| |
| size<r>::value == size<s>::value + 1 |
| |
| |
| Complexity |
| ---------- |
| |
| Amortized constant time. |
| |
| |
| Example |
| ------- |
| |
| .. parsed-literal:: |
| |
| typedef vector_c<bool,false,false,false, |
| true,true,true,false,false> bools; |
| |
| typedef push_back<bools,false_>::type message; |
| |
| BOOST_MPL_ASSERT_RELATION( back<message>::type::value, ==, false ); |
| BOOST_MPL_ASSERT_RELATION( |
| ( count_if<message, equal_to<_1,false_> >::value ), ==, 6 |
| ); |
| |
| |
| See also |
| -------- |
| |
| |Back Extensible Sequence|, |insert|, |pop_back|, |back|, |push_front| |
| |
| |
| .. 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) |
