ceph/src/boost/libs/type_traits/doc/is_nothrow_move_assignable.qbk

   1 [/
   2   Copyright 2007 John Maddock.
   3   Copyright 2013 Antony Polukhin.
   4   Distributed under the Boost Software License, Version 1.0.
   5   (See accompanying file LICENSE_1_0.txt or copy at
   6   http://www.boost.org/LICENSE_1_0.txt).
   7 ]
   8
   9 [section:is_nothrow_move_assignable is_nothrow_move_assignable]
  10
  11    template <class T>
  12    struct is_nothrow_move_assignable : public __tof {};
  13
  14 __inherit If `T` is a (possibly cv-qualified) type with a non-throwing move assignment-operator
  15 or a type without move assignment-operator but with non-throwing assignment-operator,
  16 then inherits from __true_type, otherwise inherits from __false_type.  Type `T`
  17 must be a complete type.
  18
  19 In other words, inherits from __true_type only if expression `variable1 = std::move(variable2)`
  20 won't throw (`variable1` and `variable2` are variables of type `T`).
  21
  22 __compat If the compiler does not support partial-specialization of class
  23 templates, then this template can not be used with function types.
  24
  25 Without some (C++11 noexcept shall work correctly) help from the compiler,
  26 `is_nothrow_move_assignable` will never report that a class or struct has a
  27 non-throwing assignment-operator; this is always safe, if possibly sub-optimal.
  28 Currently (June 2015) MSVC-12.0, Clang and GCC 4.7 have the necessary compiler support to ensure that this
  29 trait "just works".
  30
  31 __header ` #include <boost/type_traits/is_nothrow_move_assignable.hpp>` or ` #include <boost/type_traits.hpp>`
  32
  33 [endsect]
  34