1 /* Exception observers for outcome type
2 (C) 2017-2019 Niall Douglas <http://www.nedproductions.biz/> (6 commits)
3 File Created: Oct 2017
4 
5 
6 Boost Software License - Version 1.0 - August 17th, 2003
7 
8 Permission is hereby granted, free of charge, to any person or organization
9 obtaining a copy of the software and accompanying documentation covered by
10 this license (the "Software") to use, reproduce, display, distribute,
11 execute, and transmit the Software, and to prepare derivative works of the
12 Software, and to permit third-parties to whom the Software is furnished to
13 do so, all subject to the following:
14 
15 The copyright notices in the Software and this entire statement, including
16 the above license grant, this restriction and the following disclaimer,
17 must be included in all copies of the Software, in whole or in part, and
18 all derivative works of the Software, unless such copies or derivative
19 works are solely in the form of machine-executable object code generated by
20 a source language processor.
21 
22 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
23 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
24 FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
25 SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
26 FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
27 ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
28 DEALINGS IN THE SOFTWARE.
29 */
30 
31 #ifndef BOOST_OUTCOME_BASIC_OUTCOME_EXCEPTION_OBSERVERS_IMPL_HPP
32 #define BOOST_OUTCOME_BASIC_OUTCOME_EXCEPTION_OBSERVERS_IMPL_HPP
33 
34 #include "basic_outcome_exception_observers.hpp"
35 
36 #include "../policy/base.hpp"
37 
38 BOOST_OUTCOME_V2_NAMESPACE_EXPORT_BEGIN
39 
40 namespace policy
41 {
_exception(Impl && self)42   template <class R, class S, class P, class NoValuePolicy, class Impl> inline constexpr auto &&base::_exception(Impl &&self) noexcept
43   {
44     // Impl will be some internal implementation class which has no knowledge of the _ptr stored
45     // beneath it. So statically cast, preserving rvalue and constness, to the derived class.
46     using Outcome = BOOST_OUTCOME_V2_NAMESPACE::detail::rebind_type<basic_outcome<R, S, P, NoValuePolicy>, decltype(self)>;
47 #if defined(_MSC_VER) && _MSC_VER < 1920
48     // VS2017 tries a copy construction in the correct implementation despite that Outcome is always a rvalue or lvalue ref! :(
49     basic_outcome<R, S, P, NoValuePolicy> &_self = (basic_outcome<R, S, P, NoValuePolicy> &) (self);  // NOLINT
50 #else
51     Outcome _self = static_cast<Outcome>(self);  // NOLINT
52 #endif
53     return static_cast<Outcome>(_self)._ptr;
54   }
55 }  // namespace policy
56 
57 namespace detail
58 {
assume_exception()59   template <class Base, class R, class S, class P, class NoValuePolicy> inline constexpr typename basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::exception_type &basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::assume_exception() & noexcept
60   {
61     NoValuePolicy::narrow_exception_check(*this);
62     return NoValuePolicy::template _exception<R, S, P, NoValuePolicy>(*this);
63   }
assume_exception() const64   template <class Base, class R, class S, class P, class NoValuePolicy> inline constexpr const typename basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::exception_type &basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::assume_exception() const &noexcept
65   {
66     NoValuePolicy::narrow_exception_check(*this);
67     return NoValuePolicy::template _exception<R, S, P, NoValuePolicy>(*this);
68   }
assume_exception()69   template <class Base, class R, class S, class P, class NoValuePolicy> inline constexpr typename basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::exception_type &&basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::assume_exception() && noexcept
70   {
71     NoValuePolicy::narrow_exception_check(std::move(*this));
72     return NoValuePolicy::template _exception<R, S, P, NoValuePolicy>(std::move(*this));
73   }
assume_exception() const74   template <class Base, class R, class S, class P, class NoValuePolicy> inline constexpr const typename basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::exception_type &&basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::assume_exception() const &&noexcept
75   {
76     NoValuePolicy::narrow_exception_check(std::move(*this));
77     return NoValuePolicy::template _exception<R, S, P, NoValuePolicy>(std::move(*this));
78   }
79 
exception()80   template <class Base, class R, class S, class P, class NoValuePolicy> inline constexpr typename basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::exception_type &basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::exception() &
81   {
82     NoValuePolicy::wide_exception_check(*this);
83     return NoValuePolicy::template _exception<R, S, P, NoValuePolicy>(*this);
84   }
exception() const85   template <class Base, class R, class S, class P, class NoValuePolicy> inline constexpr const typename basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::exception_type &basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::exception() const &
86   {
87     NoValuePolicy::wide_exception_check(*this);
88     return NoValuePolicy::template _exception<R, S, P, NoValuePolicy>(*this);
89   }
exception()90   template <class Base, class R, class S, class P, class NoValuePolicy> inline constexpr typename basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::exception_type &&basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::exception() &&
91   {
92     NoValuePolicy::wide_exception_check(std::move(*this));
93     return NoValuePolicy::template _exception<R, S, P, NoValuePolicy>(std::move(*this));
94   }
exception() const95   template <class Base, class R, class S, class P, class NoValuePolicy> inline constexpr const typename basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::exception_type &&basic_outcome_exception_observers<Base, R, S, P, NoValuePolicy>::exception() const &&
96   {
97     NoValuePolicy::wide_exception_check(std::move(*this));
98     return NoValuePolicy::template _exception<R, S, P, NoValuePolicy>(std::move(*this));
99   }
100 }  // namespace detail
101 
102 BOOST_OUTCOME_V2_NAMESPACE_END
103 
104 #endif
105