ceph/src/boost/libs/core/doc/noncopyable.qbk

   1 [/
   2   Copyright 1999-2003 Beman Dawes
   3   Copyright 2014 Peter Dimov
   4
   5   Distributed under the Boost Software License, Version 1.0.
   6
   7   See accompanying file LICENSE_1_0.txt
   8   or copy at http://boost.org/LICENSE_1_0.txt
   9 ]
  10
  11 [section:noncopyable noncopyable]
  12
  13 [simplesect Authors]
  14
  15 * Dave Abrahams
  16
  17 [endsimplesect]
  18
  19 [section Header <boost/core/noncopyable.hpp>]
  20
  21 The header `<boost/noncopyable.hpp>` defines the class
  22 `boost::noncopyable`. It is intended to be used as a private
  23 base. `boost::noncopyable` has private (under C++03) or
  24 deleted (under C++11) copy constructor and a copy assignment
  25 operator and can't be copied or assigned; a class that derives
  26 from it inherits these properties.
  27
  28 `boost::noncopyable` was originally contributed by Dave
  29 Abrahams.
  30
  31 [section Synopsis]
  32
  33 ``
  34 namespace boost
  35 {
  36     class noncopyable;
  37 }
  38 ``
  39
  40 [endsect]
  41
  42 [section Example]
  43
  44 ``
  45 #include <boost/core/noncopyable.hpp>
  46
  47 class X: private boost::noncopyable
  48 {
  49 };
  50 ``
  51
  52 [endsect]
  53
  54 [section Rationale]
  55
  56 Class noncopyable has protected constructor and destructor members to emphasize
  57 that it is to be used only as a base class. Dave Abrahams notes concern about
  58 the effect on compiler optimization of adding (even trivial inline) destructor
  59 declarations. He says:
  60
  61 ["Probably this concern is misplaced, because `noncopyable` will be used mostly
  62 for classes which own resources and thus have non-trivial destruction semantics.]
  63
  64 With C++2011, using an optimized and trivial constructor and similar destructor
  65 can be enforced by declaring both and marking them `default`. This is done in
  66 the current implementation.
  67
  68 [endsect]
  69
  70 [endsect]
  71
  72 [endsect]