blob: 28204b6e31581f63a1c9c88908cce2302f930414 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
|
/*!
@file
Defines `boost::hana::accessors`.
@copyright Louis Dionne 2013-2017
Distributed under the Boost Software License, Version 1.0.
(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
*/
#ifndef BOOST_HANA_ACCESSORS_HPP
#define BOOST_HANA_ACCESSORS_HPP
#include <boost/hana/fwd/accessors.hpp>
#include <boost/hana/concept/struct.hpp>
#include <boost/hana/config.hpp>
#include <boost/hana/core/dispatch.hpp>
BOOST_HANA_NAMESPACE_BEGIN
template <typename S>
struct accessors_t {
#ifndef BOOST_HANA_CONFIG_DISABLE_CONCEPT_CHECKS
static_assert(hana::Struct<S>::value,
"hana::accessors<S> requires 'S' to be a Struct");
#endif
constexpr decltype(auto) operator()() const {
using Accessors = BOOST_HANA_DISPATCH_IF(accessors_impl<S>,
hana::Struct<S>::value
);
return Accessors::apply();
}
};
template <typename S, bool condition>
struct accessors_impl<S, when<condition>> : default_ {
template <typename ...Args>
static constexpr auto apply(Args&& ...) = delete;
};
namespace struct_detail {
template <typename ...>
struct is_valid { static constexpr bool value = true; };
}
template <typename S>
struct accessors_impl<S, when<
struct_detail::is_valid<typename S::hana_accessors_impl>::value
>>
: S::hana_accessors_impl
{ };
BOOST_HANA_NAMESPACE_END
#endif // !BOOST_HANA_ACCESSORS_HPP
|
