1/*!
2@file
3Defines `boost::hana::detail::variadic::foldr1`.
4
5Copyright Louis Dionne 2013-2022
6Distributed under the Boost Software License, Version 1.0.
7(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
8 */
9
10#ifndef BOOST_HANA_DETAIL_VARIADIC_FOLDR1_HPP
11#define BOOST_HANA_DETAIL_VARIADIC_FOLDR1_HPP
12
13#include <boost/hana/config.hpp>
14#include <boost/hana/core/when.hpp>
15
16
17namespace boost { namespace hana { namespace detail { namespace variadic {
18 //! @cond
19 template <unsigned int n, typename = when<true>>
20 struct foldr1_impl;
21
22 template <>
23 struct foldr1_impl<1> {
24 template <typename F, typename X1>
25 static constexpr X1 apply(F&&, X1&& x1)
26 { return static_cast<X1&&>(x1); }
27 };
28
29 template <>
30 struct foldr1_impl<2> {
31 template <typename F, typename X1, typename X2>
32 static constexpr decltype(auto) apply(F&& f, X1&& x1, X2&& x2) {
33 return static_cast<F&&>(f)(static_cast<X1&&>(x1),
34 static_cast<X2&&>(x2));
35 }
36 };
37
38 template <>
39 struct foldr1_impl<3> {
40 template <typename F, typename X1, typename X2, typename X3>
41 static constexpr decltype(auto) apply(F&& f, X1&& x1, X2&& x2, X3&& x3) {
42 return f(static_cast<X1&&>(x1),
43 f(static_cast<X2&&>(x2),
44 static_cast<X3&&>(x3)));
45 }
46 };
47
48 template <>
49 struct foldr1_impl<4> {
50 template <typename F, typename X1, typename X2, typename X3, typename X4>
51 static constexpr decltype(auto) apply(F&& f, X1&& x1, X2&& x2, X3&& x3, X4&& x4) {
52 return f(static_cast<X1&&>(x1),
53 f(static_cast<X2&&>(x2),
54 f(static_cast<X3&&>(x3),
55 static_cast<X4&&>(x4))));
56 }
57 };
58
59 template <>
60 struct foldr1_impl<5> {
61 template <typename F, typename X1, typename X2, typename X3, typename X4, typename X5>
62 static constexpr decltype(auto) apply(F&& f, X1&& x1, X2&& x2, X3&& x3, X4&& x4, X5&& x5) {
63 return f(static_cast<X1&&>(x1),
64 f(static_cast<X2&&>(x2),
65 f(static_cast<X3&&>(x3),
66 f(static_cast<X4&&>(x4),
67 static_cast<X5&&>(x5)))));
68 }
69 };
70
71 template <>
72 struct foldr1_impl<6> {
73 template <typename F, typename X1, typename X2, typename X3, typename X4, typename X5, typename X6>
74 static constexpr decltype(auto) apply(F&& f, X1&& x1, X2&& x2, X3&& x3, X4&& x4, X5&& x5, X6&& x6) {
75 return f(static_cast<X1&&>(x1),
76 f(static_cast<X2&&>(x2),
77 f(static_cast<X3&&>(x3),
78 f(static_cast<X4&&>(x4),
79 f(static_cast<X5&&>(x5),
80 static_cast<X6&&>(x6))))));
81 }
82 };
83
84 template <unsigned int n>
85 struct foldr1_impl<n, when<(n >= 7) && (n < 14)>> {
86 template <typename F, typename X1, typename X2, typename X3, typename X4, typename X5, typename X6, typename X7, typename ...Xn>
87 static constexpr decltype(auto)
88 apply(F&& f
89 , X1&& x1, X2&& x2, X3&& x3, X4&& x4, X5&& x5, X6&& x6, X7&& x7
90 , Xn&& ...xn)
91 {
92 return f(static_cast<X1&&>(x1),
93 f(static_cast<X2&&>(x2),
94 f(static_cast<X3&&>(x3),
95 f(static_cast<X4&&>(x4),
96 f(static_cast<X5&&>(x5),
97 f(static_cast<X6&&>(x6),
98 foldr1_impl<sizeof...(xn) + 1>::apply(f, static_cast<X7&&>(x7), static_cast<Xn&&>(xn)...)))))));
99 }
100 };
101
102 template <unsigned int n>
103 struct foldr1_impl<n, when<(n >= 14) && (n < 28)>> {
104 template <
105 typename F
106 , typename X1, typename X2, typename X3, typename X4, typename X5, typename X6, typename X7
107 , typename X8, typename X9, typename X10, typename X11, typename X12, typename X13, typename X14
108 , typename ...Xn
109 >
110 static constexpr decltype(auto)
111 apply(F&& f
112 , X1&& x1, X2&& x2, X3&& x3, X4&& x4, X5&& x5, X6&& x6, X7&& x7
113 , X8&& x8, X9&& x9, X10&& x10, X11&& x11, X12&& x12, X13&& x13, X14&& x14
114 , Xn&& ...xn)
115 {
116 return f(static_cast<X1&&>(x1), f(static_cast<X2&&>(x2), f(static_cast<X3&&>(x3), f(static_cast<X4&&>(x4), f(static_cast<X5&&>(x5), f(static_cast<X6&&>(x6), f(static_cast<X7&&>(x7),
117 f(static_cast<X8&&>(x8), f(static_cast<X9&&>(x9), f(static_cast<X10&&>(x10), f(static_cast<X11&&>(x11), f(static_cast<X12&&>(x12), f(static_cast<X13&&>(x13),
118 foldr1_impl<sizeof...(xn) + 1>::apply(f, static_cast<X14&&>(x14), static_cast<Xn&&>(xn)...))))))))))))));
119 }
120 };
121
122 template <unsigned int n>
123 struct foldr1_impl<n, when<(n >= 28) && (n < 56)>> {
124 template <
125 typename F
126 , typename X1, typename X2, typename X3, typename X4, typename X5, typename X6, typename X7
127 , typename X8, typename X9, typename X10, typename X11, typename X12, typename X13, typename X14
128 , typename X15, typename X16, typename X17, typename X18, typename X19, typename X20, typename X21
129 , typename X22, typename X23, typename X24, typename X25, typename X26, typename X27, typename X28
130 , typename ...Xn
131 >
132 static constexpr decltype(auto)
133 apply(F&& f
134 , X1&& x1, X2&& x2, X3&& x3, X4&& x4, X5&& x5, X6&& x6, X7&& x7
135 , X8&& x8, X9&& x9, X10&& x10, X11&& x11, X12&& x12, X13&& x13, X14&& x14
136 , X15&& x15, X16&& x16, X17&& x17, X18&& x18, X19&& x19, X20&& x20, X21&& x21
137 , X22&& x22, X23&& x23, X24&& x24, X25&& x25, X26&& x26, X27&& x27, X28&& x28
138 , Xn&& ...xn)
139 {
140 return f(static_cast<X1&&>(x1), f(static_cast<X2&&>(x2), f(static_cast<X3&&>(x3), f(static_cast<X4&&>(x4), f(static_cast<X5&&>(x5), f(static_cast<X6&&>(x6), f(static_cast<X7&&>(x7),
141 f(static_cast<X8&&>(x8), f(static_cast<X9&&>(x9), f(static_cast<X10&&>(x10), f(static_cast<X11&&>(x11), f(static_cast<X12&&>(x12), f(static_cast<X13&&>(x13), f(static_cast<X14&&>(x14),
142 f(static_cast<X15&&>(x15), f(static_cast<X16&&>(x16), f(static_cast<X17&&>(x17), f(static_cast<X18&&>(x18), f(static_cast<X19&&>(x19), f(static_cast<X20&&>(x20), f(static_cast<X21&&>(x21),
143 f(static_cast<X22&&>(x22), f(static_cast<X23&&>(x23), f(static_cast<X24&&>(x24), f(static_cast<X25&&>(x25), f(static_cast<X26&&>(x26), f(static_cast<X27&&>(x27),
144 foldr1_impl<sizeof...(xn) + 1>::apply(f, static_cast<X28&&>(x28), static_cast<Xn&&>(xn)...))))))))))))))))))))))))))));
145 }
146 };
147
148 template <unsigned int n>
149 struct foldr1_impl<n, when<(n >= 56)>> {
150 template <
151 typename F
152 , typename X1, typename X2, typename X3, typename X4, typename X5, typename X6, typename X7
153 , typename X8, typename X9, typename X10, typename X11, typename X12, typename X13, typename X14
154 , typename X15, typename X16, typename X17, typename X18, typename X19, typename X20, typename X21
155 , typename X22, typename X23, typename X24, typename X25, typename X26, typename X27, typename X28
156 , typename X29, typename X30, typename X31, typename X32, typename X33, typename X34, typename X35
157 , typename X36, typename X37, typename X38, typename X39, typename X40, typename X41, typename X42
158 , typename X43, typename X44, typename X45, typename X46, typename X47, typename X48, typename X49
159 , typename X50, typename X51, typename X52, typename X53, typename X54, typename X55, typename X56
160 , typename ...Xn
161 >
162 static constexpr decltype(auto)
163 apply(F&& f
164 , X1&& x1, X2&& x2, X3&& x3, X4&& x4, X5&& x5, X6&& x6, X7&& x7
165 , X8&& x8, X9&& x9, X10&& x10, X11&& x11, X12&& x12, X13&& x13, X14&& x14
166 , X15&& x15, X16&& x16, X17&& x17, X18&& x18, X19&& x19, X20&& x20, X21&& x21
167 , X22&& x22, X23&& x23, X24&& x24, X25&& x25, X26&& x26, X27&& x27, X28&& x28
168 , X29&& x29, X30&& x30, X31&& x31, X32&& x32, X33&& x33, X34&& x34, X35&& x35
169 , X36&& x36, X37&& x37, X38&& x38, X39&& x39, X40&& x40, X41&& x41, X42&& x42
170 , X43&& x43, X44&& x44, X45&& x45, X46&& x46, X47&& x47, X48&& x48, X49&& x49
171 , X50&& x50, X51&& x51, X52&& x52, X53&& x53, X54&& x54, X55&& x55, X56&& x56
172 , Xn&& ...xn)
173 {
174 return f(static_cast<X1&&>(x1), f(static_cast<X2&&>(x2), f(static_cast<X3&&>(x3), f(static_cast<X4&&>(x4), f(static_cast<X5&&>(x5), f(static_cast<X6&&>(x6), f(static_cast<X7&&>(x7),
175 f(static_cast<X8&&>(x8), f(static_cast<X9&&>(x9), f(static_cast<X10&&>(x10), f(static_cast<X11&&>(x11), f(static_cast<X12&&>(x12), f(static_cast<X13&&>(x13), f(static_cast<X14&&>(x14),
176 f(static_cast<X15&&>(x15), f(static_cast<X16&&>(x16), f(static_cast<X17&&>(x17), f(static_cast<X18&&>(x18), f(static_cast<X19&&>(x19), f(static_cast<X20&&>(x20), f(static_cast<X21&&>(x21),
177 f(static_cast<X22&&>(x22), f(static_cast<X23&&>(x23), f(static_cast<X24&&>(x24), f(static_cast<X25&&>(x25), f(static_cast<X26&&>(x26), f(static_cast<X27&&>(x27), f(static_cast<X28&&>(x28),
178 f(static_cast<X29&&>(x29), f(static_cast<X30&&>(x30), f(static_cast<X31&&>(x31), f(static_cast<X32&&>(x32), f(static_cast<X33&&>(x33), f(static_cast<X34&&>(x34), f(static_cast<X35&&>(x35),
179 f(static_cast<X36&&>(x36), f(static_cast<X37&&>(x37), f(static_cast<X38&&>(x38), f(static_cast<X39&&>(x39), f(static_cast<X40&&>(x40), f(static_cast<X41&&>(x41), f(static_cast<X42&&>(x42),
180 f(static_cast<X43&&>(x43), f(static_cast<X44&&>(x44), f(static_cast<X45&&>(x45), f(static_cast<X46&&>(x46), f(static_cast<X47&&>(x47), f(static_cast<X48&&>(x48), f(static_cast<X49&&>(x49),
181 f(static_cast<X50&&>(x50), f(static_cast<X51&&>(x51), f(static_cast<X52&&>(x52), f(static_cast<X53&&>(x53), f(static_cast<X54&&>(x54), f(static_cast<X55&&>(x55),
182 foldr1_impl<sizeof...(xn) + 1>::apply(f, static_cast<X56&&>(x56), static_cast<Xn&&>(xn)...))))))))))))))))))))))))))))))))))))))))))))))))))))))));
183 }
184 };
185 //! @endcond
186
187 struct foldr1_t {
188 template <typename F, typename X1, typename ...Xn>
189 constexpr decltype(auto) operator()(F&& f, X1&& x1, Xn&& ...xn) const {
190 return foldr1_impl<sizeof...(xn) + 1>::apply(
191 static_cast<F&&>(f), static_cast<X1&&>(x1), static_cast<Xn&&>(xn)...
192 );
193 }
194 };
195
196 BOOST_HANA_INLINE_VARIABLE constexpr foldr1_t foldr1{};
197
198 struct foldr_t {
199 template <typename F, typename State, typename ...Xn>
200 constexpr decltype(auto) operator()(F&& f, State&& state, Xn&& ...xn) const {
201 return foldr1_impl<sizeof...(xn) + 1>::apply(
202 static_cast<F&&>(f), static_cast<Xn&&>(xn)..., static_cast<State&&>(state)
203 );
204 }
205 };
206
207 BOOST_HANA_INLINE_VARIABLE constexpr foldr_t foldr{};
208}} }} // end namespace boost::hana
209
210#endif // !BOOST_HANA_DETAIL_VARIADIC_FOLDR1_HPP
211

source code of boost/libs/hana/include/boost/hana/detail/variadic/foldr1.hpp