ceph/src/boost/libs/mpl/doc/src/refmanual/negate.rst

   1 .. Metafunctions/Arithmetic Operations//negate |60
   2
   3 negate
   4 ======
   5
   6 Synopsis
   7 --------
   8
   9 .. parsed-literal::
  10
  11     template<
  12           typename T
  13         >
  14     struct negate
  15     {
  16         typedef |unspecified| type;
  17     };
  18
  19
  20
  21 Description
  22 -----------
  23
  24 Returns the negative (additive inverse) of its argument.
  25
  26
  27 Header
  28 ------
  29
  30 .. parsed-literal::
  31
  32     #include <boost/mpl/negate.hpp>
  33     #include <boost/mpl/arithmetic.hpp>
  34
  35
  36 Model of
  37 --------
  38
  39 |Numeric Metafunction|
  40
  41
  42 Parameters
  43 ----------
  44
  45 +---------------+---------------------------+-----------------------------------------------+
  46 | Parameter     | Requirement               | Description                                   |
  47 +===============+===========================+===============================================+
  48 | ``T``         | |Integral Constant|       | Operation's argument.                         |
  49 +---------------+---------------------------+-----------------------------------------------+
  50
  51 |Note:| |numeric metafunction note| |-- end note|
  52
  53
  54 Expression semantics
  55 --------------------
  56
  57 For any |Integral Constant| ``c``:
  58
  59 .. parsed-literal::
  60
  61     typedef negate<c>::type r;
  62
  63 :Return type:
  64     |Integral Constant|.
  65
  66 :Semantics:
  67     Equivalent to
  68
  69     .. parsed-literal::
  70
  71         typedef integral_c< c::value_type, ( -c::value ) > r;
  72
  73 .. ..........................................................................
  74
  75 .. parsed-literal::
  76
  77     typedef negate<c> r;
  78
  79 :Return type:
  80     |Integral Constant|.
  81
  82 :Semantics:
  83     Equivalent to
  84
  85     .. parsed-literal::
  86
  87         struct r : negate<c>::type {};
  88
  89
  90 Complexity
  91 ----------
  92
  93 Amortized constant time.
  94
  95
  96 Example
  97 -------
  98
  99 .. parsed-literal::
 100
 101     typedef negate< int_<-10> >::type r;
 102     BOOST_MPL_ASSERT_RELATION( r::value, ==, 10 );
 103     BOOST_MPL_ASSERT(( is_same< r::value_type, int > ));
 104
 105
 106 See also
 107 --------
 108
 109 |Arithmetic Operations|, |Numeric Metafunction|, |numeric_cast|, |plus|, |minus|, |times|
 110
 111
 112 .. copyright:: Copyright ©  2001-2009 Aleksey Gurtovoy and David Abrahams
 113    Distributed under the Boost Software License, Version 1.0. (See accompanying
 114    file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)