ceph/src/boost/boost/callable_traits/is_transaction_safe.hpp

   1 /*
   2 @file is_transaction_safe
   3
   4 @Copyright Barrett Adair 2015-2017
   5 Distributed under the Boost Software License, Version 1.0.
   6 (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
   7
   8 */
   9
  10 #ifndef BOOST_CLBL_TRTS_IS_TRANSACTION_SAFE_HPP
  11 #define BOOST_CLBL_TRTS_IS_TRANSACTION_SAFE_HPP
  12
  13 #include <boost/callable_traits/detail/core.hpp>
  14
  15 namespace boost { namespace callable_traits {
  16
  17 //[ is_transaction_safe_hpp
  18 /*`[section:ref_is_transaction_safe is_transaction_safe]
  19 [heading Header]
  20 ``#include <boost/callable_traits/is_transaction_safe.hpp>``
  21 [heading Definition]
  22 */
  23
  24
  25 // inherits from either std::true_type or std::false_type
  26 template<typename T>
  27 struct is_transaction_safe;
  28
  29 //<-
  30 template<typename T>
  31 struct is_transaction_safe : detail::traits<
  32     detail::shallow_decay<T>>::is_transaction_safe {
  33
  34     using type = typename detail::traits<
  35         detail::shallow_decay<T>>::is_transaction_safe;
  36 };
  37
  38 #ifdef BOOST_CLBL_TRTS_DISABLE_VARIABLE_TEMPLATES
  39
  40 template<typename T>
  41 struct is_transaction_safe_v {
  42     static_assert(std::is_same<T, detail::dummy>::value,
  43         "Variable templates not supported on this compiler.");
  44 };
  45
  46 #else
  47 //->
  48 // only available when variable templates are supported
  49 template<typename T>
  50 //<-
  51 BOOST_CLBL_TRAITS_INLINE_VAR
  52 //->
  53 constexpr bool is_transaction_safe_v = //see below
  54 //<-
  55     detail::traits<detail::shallow_decay<T>>::is_transaction_safe::value;
  56
  57 #endif
  58
  59 }} // namespace boost::callable_traits
  60 //->
  61
  62 /*`
  63 [heading Constraints]
  64 * none
  65 *
  66 [heading Behavior]
  67 * `is_transaction_safe<T>::value` is `true` when either:
  68   * `T` is a function type, function pointer type, function reference type, or member function pointer type where the function has a `transaction_safe` specifier
  69   * `T` is a function object with a non-overloaded `operator()`, where the `operator()` has a `transaction_safe` specifier
  70 * On compilers that support variable templates, `is_transaction_safe_v<T>` is equivalent to `is_transaction_safe<T>::value`.
  71
  72 [heading Input/Output Examples]
  73 [table
  74     [[`T`]                              [`is_transaction_safe_v<T>`]]
  75     [[`int() const transaction_safe`]   [`true`]]
  76     [[`int(*)() transaction_safe`]      [`true`]]
  77     [[`int(&)() transaction_safe`]      [`true`]]
  78     [[`int(foo::* const)() transaction_safe`] [`true`]]
  79     [[`int() const`]                    [`false`]]
  80     [[`int() volatile`]                 [`false`]]
  81     [[`int(foo::*)() const`]            [`false`]]
  82     [[`int() const`]                    [`false`]]
  83     [[`int() volatile`]                 [`false`]]
  84     [[`int() &`]                        [`false`]]
  85     [[`int(*)()`]                       [`false`]]
  86     [[`int`]                            [`false`]]
  87     [[`int foo::*`]                     [`false`]]
  88     [[`const int foo::*`]               [`false`]]
  89 ]
  90
  91 [heading Example Program]
  92 [import ../example/is_transaction_safe.cpp]
  93 [is_transaction_safe]
  94 [endsect]
  95 */
  96 //]
  97
  98 #endif // #ifndef BOOST_CLBL_TRTS_IS_TRANSACTION_SAFE_HPP