projects / ceph.git / blame
| Commit | Line | Data |
|---|---|---|
| 7c673cae FG |
1 | .. Algorithms/Querying Algorithms//find |10 |
| 2 | ||
| 3 | find | |
| 4 | ==== | |
| 5 | ||
| 6 | Synopsis | |
| 7 | -------- | |
| 8 | ||
| 9 | .. parsed-literal:: | |
| 10 | ||
| 11 | template< | |
| 12 | typename Sequence | |
| 13 | , typename T | |
| 14 | > | |
| 15 | struct find | |
| 16 | { | |
| 17 | typedef |unspecified| type; | |
| 18 | }; | |
| 19 | ||
| 20 | ||
| 21 | ||
| 22 | Description | |
| 23 | ----------- | |
| 24 | ||
| 25 | Returns an iterator to the first occurrence of type ``T`` in a ``Sequence``. | |
| 26 | ||
| 27 | ||
| 28 | Header | |
| 29 | ------ | |
| 30 | ||
| 31 | .. parsed-literal:: | |
| 32 | ||
| 33 | #include <boost/mpl/find.hpp> | |
| 34 | ||
| 35 | ||
| 36 | ||
| 37 | Parameters | |
| 38 | ---------- | |
| 39 | ||
| 40 | +---------------+-----------------------+-----------------------------------+ | |
| 41 | | Parameter | Requirement | Description | | |
| 42 | +===============+=======================+===================================+ | |
| 43 | | ``Sequence`` | |Forward Sequence| | A sequence to search in. | | |
| 44 | +---------------+-----------------------+-----------------------------------+ | |
| 45 | | ``T`` | Any type | A type to search for. | | |
| 46 | +---------------+-----------------------+-----------------------------------+ | |
| 47 | ||
| 48 | ||
| 49 | Expression semantics | |
| 50 | -------------------- | |
| 51 | ||
| 52 | For any |Forward Sequence| ``s`` and arbitrary type ``t``: | |
| 53 | ||
| 54 | ||
| 55 | .. parsed-literal:: | |
| 56 | ||
| 57 | typedef find<s,t>::type i; | |
| 58 | ||
| 59 | ||
| 60 | :Return type: | |
| 61 | |Forward Iterator|. | |
| 62 | ||
| 63 | :Semantics: | |
| 64 | Equivalent to | |
| 65 | ||
| 66 | .. parsed-literal:: | |
| 67 | ||
| 68 | typedef find_if<s, is_same<_,t> >::type i; | |
| 69 | ||
| 70 | ||
| 71 | Complexity | |
| 72 | ---------- | |
| 73 | ||
| 74 | Linear. At most ``size<s>::value`` comparisons for identity. | |
| 75 | ||
| 76 | ||
| 77 | Example | |
| 78 | ------- | |
| 79 | ||
| 80 | .. parsed-literal:: | |
| 81 | ||
| 82 | typedef vector<char,int,unsigned,long,unsigned long> types; | |
| 83 | typedef find<types,unsigned>::type iter; | |
| 84 | ||
| 85 | BOOST_MPL_ASSERT(( is_same< deref<iter>::type, unsigned > )); | |
| 86 | BOOST_MPL_ASSERT_RELATION( iter::pos::value, ==, 2 ); | |
| 87 | ||
| 88 | ||
| 89 | See also | |
| 90 | -------- | |
| 91 | ||
| 92 | |Querying Algorithms|, |contains|, |find_if|, |count|, |lower_bound| | |
| 93 | ||
| 94 | ||
| 95 |