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

   1 .. Metafunctions/Logical Operations//not_ |30
   2
   3 not\_
   4 =====
   5
   6 Synopsis
   7 --------
   8
   9 .. parsed-literal::
  10
  11     template<
  12           typename F
  13         >
  14     struct not\_
  15     {
  16         typedef |unspecified| type;
  17     };
  18
  19
  20
  21 Description
  22 -----------
  23
  24 Returns the result of *logical not* (``!``) operation on its argument.
  25
  26
  27 Header
  28 ------
  29
  30 .. parsed-literal::
  31
  32     #include <boost/mpl/not.hpp>
  33     #include <boost/mpl/logical.hpp>
  34
  35
  36 Parameters
  37 ----------
  38
  39 +---------------+---------------------------+-----------------------------------------------+
  40 | Parameter     | Requirement               | Description                                   |
  41 +===============+===========================+===============================================+
  42 | ``F``         | Nullary |Metafunction|    | Operation's argument.                         |
  43 +---------------+---------------------------+-----------------------------------------------+
  44
  45
  46 Expression semantics
  47 --------------------
  48
  49 For arbitrary nullary |Metafunction| ``f``:
  50
  51 .. parsed-literal::
  52
  53     typedef not_<f>::type r;
  54
  55 :Return type:
  56     |Integral Constant|.
  57
  58 :Semantics:
  59     Equivalent to
  60
  61     .. parsed-literal::
  62
  63         typedef bool_< (!f::type::value) > r;
  64
  65 .. ..........................................................................
  66
  67 .. parsed-literal::
  68
  69     typedef not_<f> r;
  70
  71 :Return type:
  72     |Integral Constant|.
  73
  74 :Semantics:
  75     Equivalent to
  76
  77     .. parsed-literal::
  78
  79         struct r : not_<f>::type {};
  80
  81
  82 Example
  83 -------
  84
  85 .. parsed-literal::
  86
  87     BOOST_MPL_ASSERT_NOT(( not_< true\_ > ));
  88     BOOST_MPL_ASSERT(( not_< false\_ > ));
  89
  90
  91 See also
  92 --------
  93
  94 |Metafunctions|, |Logical Operations|, |and_|, |or_|
  95
  96
  97 .. copyright:: Copyright ©  2001-2009 Aleksey Gurtovoy and David Abrahams
  98    Distributed under the Boost Software License, Version 1.0. (See accompanying
  99    file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)