projects / ceph.git / blame
| Commit | Line | Data |
|---|---|---|
| 7c673cae FG |
1 | .. Sequences/Intrinsic Metafunctions//push_back |
| 2 | ||
| 3 | push_back | |
| 4 | ========= | |
| 5 | ||
| 6 | Synopsis | |
| 7 | -------- | |
| 8 | ||
| 9 | .. parsed-literal:: | |
| 10 | ||
| 11 | template< | |
| 12 | typename Sequence | |
| 13 | , typename T | |
| 14 | > | |
| 15 | struct push_back | |
| 16 | { | |
| 17 | typedef |unspecified| type; | |
| 18 | }; | |
| 19 | ||
| 20 | ||
| 21 | ||
| 22 | Description | |
| 23 | ----------- | |
| 24 | ||
| 25 | ``push_back`` performs an insertion at the end of the sequence with guaranteed |O(1)| | |
| 26 | complexity. | |
| 27 | ||
| 28 | Header | |
| 29 | ------ | |
| 30 | ||
| 31 | .. parsed-literal:: | |
| 32 | ||
| 33 | #include <boost/mpl/push_back.hpp> | |
| 34 | ||
| 35 | ||
| 36 | ||
| 37 | Model of | |
| 38 | -------- | |
| 39 | ||
| 40 | |Tag Dispatched Metafunction| | |
| 41 | ||
| 42 | ||
| 43 | Parameters | |
| 44 | ---------- | |
| 45 | ||
| 46 | +---------------+-------------------------------+-----------------------------------------------+ | |
| 47 | | Parameter | Requirement | Description | | |
| 48 | +===============+===============================+===============================================+ | |
| 49 | | ``Sequence`` | |Back Extensible Sequence| | A sequence to insert into. | | |
| 50 | +---------------+-------------------------------+-----------------------------------------------+ | |
| 51 | | ``T`` | Any type | The element to be inserted. | | |
| 52 | +---------------+-------------------------------+-----------------------------------------------+ | |
| 53 | ||
| 54 | ||
| 55 | Expression semantics | |
| 56 | -------------------- | |
| 57 | ||
| 58 | For any |Back Extensible Sequence| ``s`` and arbitrary type ``x``: | |
| 59 | ||
| 60 | ||
| 61 | .. parsed-literal:: | |
| 62 | ||
| 63 | typedef push_back<s,x>::type r; | |
| 64 | ||
| 65 | :Return type: | |
| 66 | |Back Extensible Sequence|. | |
| 67 | ||
| 68 | :Semantics: | |
| 69 | Equivalent to | |
| 70 | ||
| 71 | .. parsed-literal:: | |
| 72 | ||
| 73 | typedef insert< s,end<s>::type,x >::type r; | |
| 74 | ||
| 75 | ||
| 76 | :Postcondition: | |
| 77 | ``back<r>::type`` is identical to ``x``; | |
| 78 | ||
| 79 | .. parsed-literal:: | |
| 80 | ||
| 81 | size<r>::value == size<s>::value + 1 | |
| 82 | ||
| 83 | ||
| 84 | Complexity | |
| 85 | ---------- | |
| 86 | ||
| 87 | Amortized constant time. | |
| 88 | ||
| 89 | ||
| 90 | Example | |
| 91 | ------- | |
| 92 | ||
| 93 | .. parsed-literal:: | |
| 94 | ||
| 95 | typedef vector_c<bool,false,false,false, | |
| 96 | true,true,true,false,false> bools; | |
| 97 | ||
| 98 | typedef push_back<bools,false_>::type message; | |
| 99 | ||
| 100 | BOOST_MPL_ASSERT_RELATION( back<message>::type::value, ==, false ); | |
| 101 | BOOST_MPL_ASSERT_RELATION( | |
| 102 | ( count_if<message, equal_to<_1,false_> >::value ), ==, 6 | |
| 103 | ); | |
| 104 | ||
| 105 | ||
| 106 | See also | |
| 107 | -------- | |
| 108 | ||
| 109 | |Back Extensible Sequence|, |insert|, |pop_back|, |back|, |push_front| | |
| 110 | ||
| 111 | ||
| 112 |