ceph/src/boost/boost/callable_traits/has_member_qualifiers.hpp

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