projects / ceph.git / blame
| Commit | Line | Data |
|---|---|---|
| 7c673cae FG |
1 | .. Metafunctions/Arithmetic Operations//plus |10 |
| 2 | ||
| 3 | plus | |
| 4 | ==== | |
| 5 | ||
| 6 | Synopsis | |
| 7 | -------- | |
| 8 | ||
| 9 | .. parsed-literal:: | |
| 10 | ||
| 11 | template< | |
| 12 | typename T1 | |
| 13 | , typename T2 | |
| 14 | , typename T3 = |unspecified| | |
| 15 | |...| | |
| 16 | , typename T\ *n* = |unspecified| | |
| 17 | > | |
| 18 | struct plus | |
| 19 | { | |
| 20 | typedef |unspecified| type; | |
| 21 | }; | |
| 22 | ||
| 23 | ||
| 24 | ||
| 25 | Description | |
| 26 | ----------- | |
| 27 | ||
| 28 | Returns the sum of its arguments. | |
| 29 | ||
| 30 | ||
| 31 | Header | |
| 32 | ------ | |
| 33 | ||
| 34 | .. parsed-literal:: | |
| 35 | ||
| 36 | #include <boost/mpl/plus.hpp> | |
| 37 | #include <boost/mpl/arithmetic.hpp> | |
| 38 | ||
| 39 | ||
| 40 | Model of | |
| 41 | -------- | |
| 42 | ||
| 43 | |Numeric Metafunction| | |
| 44 | ||
| 45 | ||
| 46 | ||
| 47 | Parameters | |
| 48 | ---------- | |
| 49 | ||
| 50 | +---------------+---------------------------+-----------------------------------------------+ | |
| 51 | | Parameter | Requirement | Description | | |
| 52 | +===============+===========================+===============================================+ | |
| 53 | | |T1...Tn| | |Integral Constant| | Operation's arguments. | | |
| 54 | +---------------+---------------------------+-----------------------------------------------+ | |
| 55 | ||
| 56 | |Note:| |numeric metafunction note| |-- end note| | |
| 57 | ||
| 58 | ||
| 59 | Expression semantics | |
| 60 | -------------------- | |
| 61 | ||
| 62 | For any |Integral Constant|\ s |c1...cn|: | |
| 63 | ||
| 64 | ||
| 65 | .. parsed-literal:: | |
| 66 | ||
| 67 | typedef plus<c1,\ |...|\ c\ *n*\>::type r; | |
| 68 | ||
| 69 | :Return type: | |
| 70 | |Integral Constant|. | |
| 71 | ||
| 72 | :Semantics: | |
| 73 | Equivalent to | |
| 74 | ||
| 75 | .. parsed-literal:: | |
| 76 | ||
| 77 | typedef integral_c< | |
| 78 | typeof(c1::value + c2::value) | |
| 79 | , ( c1::value + c2::value ) | |
| 80 | > c; | |
| 81 | ||
| 82 | typedef plus<c,c3,\ |...|\c\ *n*\>::type r; | |
| 83 | ||
| 84 | .. .......................................................................... | |
| 85 | ||
| 86 | .. parsed-literal:: | |
| 87 | ||
| 88 | typedef plus<c1,\ |...|\ c\ *n*\> r; | |
| 89 | ||
| 90 | :Return type: | |
| 91 | |Integral Constant|. | |
| 92 | ||
| 93 | :Semantics: | |
| 94 | Equivalent to | |
| 95 | ||
| 96 | .. parsed-literal:: | |
| 97 | ||
| 98 | struct r : plus<c1,\ |...|\ c\ *n*\>::type {}; | |
| 99 | ||
| 100 | ||
| 101 | ||
| 102 | ||
| 103 | Complexity | |
| 104 | ---------- | |
| 105 | ||
| 106 | Amortized constant time. | |
| 107 | ||
| 108 | ||
| 109 | Example | |
| 110 | ------- | |
| 111 | ||
| 112 | .. parsed-literal:: | |
| 113 | ||
| 114 | typedef plus< int_<-10>, int_<3>, long_<1> >::type r; | |
| 115 | BOOST_MPL_ASSERT_RELATION( r::value, ==, -6 ); | |
| 116 | BOOST_MPL_ASSERT(( is_same< r::value_type, long > )); | |
| 117 | ||
| 118 | ||
| 119 | See also | |
| 120 | -------- | |
| 121 | ||
| 122 | |Arithmetic Operations|, |Numeric Metafunction|, |numeric_cast|, |minus|, |negate|, |times| | |
| 123 | ||
| 124 | ||
| 125 |