algorithm.hpp 36 KB

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  1. #ifndef BOOST_MP11_ALGORITHM_HPP_INCLUDED
  2. #define BOOST_MP11_ALGORITHM_HPP_INCLUDED
  3. // Copyright 2015-2019 Peter Dimov
  4. //
  5. // Distributed under the Boost Software License, Version 1.0.
  6. //
  7. // See accompanying file LICENSE_1_0.txt or copy at
  8. // http://www.boost.org/LICENSE_1_0.txt
  9. #include <boost/mp11/list.hpp>
  10. #include <boost/mp11/set.hpp>
  11. #include <boost/mp11/integral.hpp>
  12. #include <boost/mp11/utility.hpp>
  13. #include <boost/mp11/function.hpp>
  14. #include <boost/mp11/detail/mp_count.hpp>
  15. #include <boost/mp11/detail/mp_plus.hpp>
  16. #include <boost/mp11/detail/mp_map_find.hpp>
  17. #include <boost/mp11/detail/mp_with_index.hpp>
  18. #include <boost/mp11/detail/mp_fold.hpp>
  19. #include <boost/mp11/detail/mp_min_element.hpp>
  20. #include <boost/mp11/detail/mp_copy_if.hpp>
  21. #include <boost/mp11/detail/mp_remove_if.hpp>
  22. #include <boost/mp11/detail/config.hpp>
  23. #include <boost/mp11/integer_sequence.hpp>
  24. #include <type_traits>
  25. #include <utility>
  26. namespace boost
  27. {
  28. namespace mp11
  29. {
  30. // mp_transform<F, L...>
  31. namespace detail
  32. {
  33. template<template<class...> class F, class... L> struct mp_transform_impl
  34. {
  35. };
  36. template<template<class...> class F, template<class...> class L, class... T> struct mp_transform_impl<F, L<T...>>
  37. {
  38. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, < 1920 )
  39. template<class... U> struct f { using type = F<U...>; };
  40. using type = L<typename f<T>::type...>;
  41. #else
  42. using type = L<F<T>...>;
  43. #endif
  44. };
  45. template<template<class...> class F, template<class...> class L1, class... T1, template<class...> class L2, class... T2> struct mp_transform_impl<F, L1<T1...>, L2<T2...>>
  46. {
  47. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, < 1920 )
  48. template<class... U> struct f { using type = F<U...>; };
  49. using type = L1<typename f<T1, T2>::type...>;
  50. #else
  51. using type = L1<F<T1,T2>...>;
  52. #endif
  53. };
  54. template<template<class...> class F, template<class...> class L1, class... T1, template<class...> class L2, class... T2, template<class...> class L3, class... T3> struct mp_transform_impl<F, L1<T1...>, L2<T2...>, L3<T3...>>
  55. {
  56. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, < 1920 )
  57. template<class... U> struct f { using type = F<U...>; };
  58. using type = L1<typename f<T1, T2, T3>::type...>;
  59. #else
  60. using type = L1<F<T1,T2,T3>...>;
  61. #endif
  62. };
  63. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, == 1900 ) || BOOST_MP11_WORKAROUND( BOOST_MP11_GCC, < 40800 )
  64. template<class... L> using mp_same_size_1 = mp_same<mp_size<L>...>;
  65. template<class... L> struct mp_same_size_2: mp_defer<mp_same_size_1, L...> {};
  66. #endif
  67. struct list_size_mismatch
  68. {
  69. };
  70. #if BOOST_MP11_WORKAROUND( BOOST_MP11_CUDA, >= 9000000 && BOOST_MP11_CUDA < 10000000 )
  71. template<template<class...> class F, class... L> struct mp_transform_cuda_workaround
  72. {
  73. using type = mp_if<mp_same<mp_size<L>...>, detail::mp_transform_impl<F, L...>, detail::list_size_mismatch>;
  74. };
  75. #endif
  76. } // namespace detail
  77. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, == 1900 ) || BOOST_MP11_WORKAROUND( BOOST_MP11_GCC, < 40800 )
  78. template<template<class...> class F, class... L> using mp_transform = typename mp_if<typename detail::mp_same_size_2<L...>::type, detail::mp_transform_impl<F, L...>, detail::list_size_mismatch>::type;
  79. #else
  80. #if BOOST_MP11_WORKAROUND( BOOST_MP11_CUDA, >= 9000000 && BOOST_MP11_CUDA < 10000000 )
  81. template<template<class...> class F, class... L> using mp_transform = typename detail::mp_transform_cuda_workaround< F, L...>::type::type;
  82. #else
  83. template<template<class...> class F, class... L> using mp_transform = typename mp_if<mp_same<mp_size<L>...>, detail::mp_transform_impl<F, L...>, detail::list_size_mismatch>::type;
  84. #endif
  85. #endif
  86. template<class Q, class... L> using mp_transform_q = mp_transform<Q::template fn, L...>;
  87. namespace detail
  88. {
  89. template<template<class...> class F, template<class...> class L1, class... T1, template<class...> class L2, class... T2, template<class...> class L3, class... T3, template<class...> class L4, class... T4, class... L> struct mp_transform_impl<F, L1<T1...>, L2<T2...>, L3<T3...>, L4<T4...>, L...>
  90. {
  91. using A1 = L1<mp_list<T1, T2, T3, T4>...>;
  92. template<class V, class T> using _f = mp_transform<mp_push_back, V, T>;
  93. using A2 = mp_fold<mp_list<L...>, A1, _f>;
  94. template<class T> using _g = mp_apply<F, T>;
  95. using type = mp_transform<_g, A2>;
  96. };
  97. } // namespace detail
  98. // mp_transform_if<P, F, L...>
  99. namespace detail
  100. {
  101. template<template<class...> class P, template<class...> class F, class... L> struct mp_transform_if_impl
  102. {
  103. // the stupid quote-unquote dance avoids "pack expansion used as argument for non-pack parameter of alias template"
  104. using Qp = mp_quote<P>;
  105. using Qf = mp_quote<F>;
  106. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, < 1920 )
  107. template<class... U> struct _f_ { using type = mp_eval_if_q<mp_not<mp_invoke_q<Qp, U...>>, mp_first<mp_list<U...>>, Qf, U...>; };
  108. template<class... U> using _f = typename _f_<U...>::type;
  109. #else
  110. template<class... U> using _f = mp_eval_if_q<mp_not<mp_invoke_q<Qp, U...>>, mp_first<mp_list<U...>>, Qf, U...>;
  111. #endif
  112. using type = mp_transform<_f, L...>;
  113. };
  114. } // namespace detail
  115. template<template<class...> class P, template<class...> class F, class... L> using mp_transform_if = typename detail::mp_transform_if_impl<P, F, L...>::type;
  116. template<class Qp, class Qf, class... L> using mp_transform_if_q = typename detail::mp_transform_if_impl<Qp::template fn, Qf::template fn, L...>::type;
  117. // mp_filter<P, L...>
  118. namespace detail
  119. {
  120. template<template<class...> class P, class L1, class... L> struct mp_filter_impl
  121. {
  122. using Qp = mp_quote<P>;
  123. template<class T1, class... T> using _f = mp_if< mp_invoke_q<Qp, T1, T...>, mp_list<T1>, mp_list<> >;
  124. using _t1 = mp_transform<_f, L1, L...>;
  125. using _t2 = mp_apply<mp_append, _t1>;
  126. using type = mp_assign<L1, _t2>;
  127. };
  128. } // namespace detail
  129. template<template<class...> class P, class... L> using mp_filter = typename detail::mp_filter_impl<P, L...>::type;
  130. template<class Q, class... L> using mp_filter_q = typename detail::mp_filter_impl<Q::template fn, L...>::type;
  131. // mp_fill<L, V>
  132. namespace detail
  133. {
  134. template<class L, class V> struct mp_fill_impl;
  135. template<template<class...> class L, class... T, class V> struct mp_fill_impl<L<T...>, V>
  136. {
  137. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, <= 1900 )
  138. template<class...> struct _f { using type = V; };
  139. using type = L<typename _f<T>::type...>;
  140. #else
  141. template<class...> using _f = V;
  142. using type = L<_f<T>...>;
  143. #endif
  144. };
  145. } // namespace detail
  146. template<class L, class V> using mp_fill = typename detail::mp_fill_impl<L, V>::type;
  147. // mp_contains<L, V>
  148. template<class L, class V> using mp_contains = mp_to_bool<mp_count<L, V>>;
  149. // mp_repeat(_c)<L, N>
  150. namespace detail
  151. {
  152. template<class L, std::size_t N> struct mp_repeat_c_impl
  153. {
  154. using _l1 = typename mp_repeat_c_impl<L, N/2>::type;
  155. using _l2 = typename mp_repeat_c_impl<L, N%2>::type;
  156. using type = mp_append<_l1, _l1, _l2>;
  157. };
  158. template<class L> struct mp_repeat_c_impl<L, 0>
  159. {
  160. using type = mp_clear<L>;
  161. };
  162. template<class L> struct mp_repeat_c_impl<L, 1>
  163. {
  164. using type = L;
  165. };
  166. } // namespace detail
  167. template<class L, std::size_t N> using mp_repeat_c = typename detail::mp_repeat_c_impl<L, N>::type;
  168. template<class L, class N> using mp_repeat = typename detail::mp_repeat_c_impl<L, std::size_t{ N::value }>::type;
  169. // mp_product<F, L...>
  170. namespace detail
  171. {
  172. template<template<class...> class F, class P, class... L> struct mp_product_impl_2
  173. {
  174. };
  175. template<template<class...> class F, class P> struct mp_product_impl_2<F, P>
  176. {
  177. using type = mp_list<mp_rename<P, F>>;
  178. };
  179. template<template<class...> class F, class P, template<class...> class L1, class... T1, class... L> struct mp_product_impl_2<F, P, L1<T1...>, L...>
  180. {
  181. using type = mp_append<typename mp_product_impl_2<F, mp_push_back<P, T1>, L...>::type...>;
  182. };
  183. template<template<class...> class F, class... L> struct mp_product_impl
  184. {
  185. };
  186. template<template<class...> class F> struct mp_product_impl<F>
  187. {
  188. using type = mp_list< F<> >;
  189. };
  190. template<template<class...> class F, class L1, class... L> struct mp_product_impl<F, L1, L...>
  191. {
  192. using type = mp_assign<L1, typename mp_product_impl_2<F, mp_list<>, L1, L...>::type>;
  193. };
  194. } // namespace detail
  195. template<template<class...> class F, class... L> using mp_product = typename detail::mp_product_impl<F, L...>::type;
  196. template<class Q, class... L> using mp_product_q = typename detail::mp_product_impl<Q::template fn, L...>::type;
  197. // mp_drop(_c)<L, N>
  198. namespace detail
  199. {
  200. template<class L, class L2> struct mp_drop_impl;
  201. template<template<class...> class L, class... T, template<class...> class L2, class... U> struct mp_drop_impl<L<T...>, L2<U...>>
  202. {
  203. template<class... W> static mp_identity<L<W...>> f( U*..., mp_identity<W>*... );
  204. using R = decltype( f( (mp_identity<T>*)0 ... ) );
  205. using type = typename R::type;
  206. };
  207. } // namespace detail
  208. template<class L, std::size_t N> using mp_drop_c = typename detail::mp_drop_impl<L, mp_repeat_c<mp_list<void>, N>>::type;
  209. template<class L, class N> using mp_drop = typename detail::mp_drop_impl<L, mp_repeat<mp_list<void>, N>>::type;
  210. // mp_from_sequence<S>
  211. namespace detail
  212. {
  213. template<class S> struct mp_from_sequence_impl;
  214. template<template<class T, T... I> class S, class U, U... J> struct mp_from_sequence_impl<S<U, J...>>
  215. {
  216. using type = mp_list<std::integral_constant<U, J>...>;
  217. };
  218. } // namespace detail
  219. template<class S> using mp_from_sequence = typename detail::mp_from_sequence_impl<S>::type;
  220. // mp_iota(_c)<N>
  221. template<std::size_t N> using mp_iota_c = mp_from_sequence<make_index_sequence<N>>;
  222. template<class N> using mp_iota = mp_from_sequence<make_integer_sequence<typename std::remove_const<decltype(N::value)>::type, N::value>>;
  223. // mp_at(_c)<L, I>
  224. namespace detail
  225. {
  226. template<class L, std::size_t I> struct mp_at_c_impl;
  227. #if defined(BOOST_MP11_HAS_TYPE_PACK_ELEMENT)
  228. template<template<class...> class L, class... T, std::size_t I> struct mp_at_c_impl<L<T...>, I>
  229. {
  230. using type = __type_pack_element<I, T...>;
  231. };
  232. #else
  233. template<class L, std::size_t I> struct mp_at_c_impl
  234. {
  235. using _map = mp_transform<mp_list, mp_iota<mp_size<L> >, L>;
  236. using type = mp_second<mp_map_find<_map, mp_size_t<I> > >;
  237. };
  238. #endif
  239. #if BOOST_MP11_WORKAROUND( BOOST_MP11_CUDA, >= 9000000 && BOOST_MP11_CUDA < 10000000 )
  240. template<class L, std::size_t I> struct mp_at_c_cuda_workaround
  241. {
  242. using type = mp_if_c<(I < mp_size<L>::value), detail::mp_at_c_impl<L, I>, void>;
  243. };
  244. #endif
  245. } // namespace detail
  246. #if BOOST_MP11_WORKAROUND( BOOST_MP11_CUDA, >= 9000000 && BOOST_MP11_CUDA < 10000000 )
  247. template<class L, std::size_t I> using mp_at_c = typename detail::mp_at_c_cuda_workaround< L, I >::type::type;
  248. #else
  249. template<class L, std::size_t I> using mp_at_c = typename mp_if_c<(I < mp_size<L>::value), detail::mp_at_c_impl<L, I>, void>::type;
  250. #endif
  251. template<class L, class I> using mp_at = mp_at_c<L, std::size_t{ I::value }>;
  252. // mp_take(_c)<L, N>
  253. namespace detail
  254. {
  255. template<std::size_t N, class L, class E = void> struct mp_take_c_impl
  256. {
  257. };
  258. template<template<class...> class L, class... T>
  259. struct mp_take_c_impl<0, L<T...>>
  260. {
  261. using type = L<>;
  262. };
  263. template<template<class...> class L, class T1, class... T>
  264. struct mp_take_c_impl<1, L<T1, T...>>
  265. {
  266. using type = L<T1>;
  267. };
  268. template<template<class...> class L, class T1, class T2, class... T>
  269. struct mp_take_c_impl<2, L<T1, T2, T...>>
  270. {
  271. using type = L<T1, T2>;
  272. };
  273. template<template<class...> class L, class T1, class T2, class T3, class... T>
  274. struct mp_take_c_impl<3, L<T1, T2, T3, T...>>
  275. {
  276. using type = L<T1, T2, T3>;
  277. };
  278. template<template<class...> class L, class T1, class T2, class T3, class T4, class... T>
  279. struct mp_take_c_impl<4, L<T1, T2, T3, T4, T...>>
  280. {
  281. using type = L<T1, T2, T3, T4>;
  282. };
  283. template<template<class...> class L, class T1, class T2, class T3, class T4, class T5, class... T>
  284. struct mp_take_c_impl<5, L<T1, T2, T3, T4, T5, T...>>
  285. {
  286. using type = L<T1, T2, T3, T4, T5>;
  287. };
  288. template<template<class...> class L, class T1, class T2, class T3, class T4, class T5, class T6, class... T>
  289. struct mp_take_c_impl<6, L<T1, T2, T3, T4, T5, T6, T...>>
  290. {
  291. using type = L<T1, T2, T3, T4, T5, T6>;
  292. };
  293. template<template<class...> class L, class T1, class T2, class T3, class T4, class T5, class T6, class T7, class... T>
  294. struct mp_take_c_impl<7, L<T1, T2, T3, T4, T5, T6, T7, T...>>
  295. {
  296. using type = L<T1, T2, T3, T4, T5, T6, T7>;
  297. };
  298. template<template<class...> class L, class T1, class T2, class T3, class T4, class T5, class T6, class T7, class T8, class... T>
  299. struct mp_take_c_impl<8, L<T1, T2, T3, T4, T5, T6, T7, T8, T...>>
  300. {
  301. using type = L<T1, T2, T3, T4, T5, T6, T7, T8>;
  302. };
  303. template<template<class...> class L, class T1, class T2, class T3, class T4, class T5, class T6, class T7, class T8, class T9, class... T>
  304. struct mp_take_c_impl<9, L<T1, T2, T3, T4, T5, T6, T7, T8, T9, T...>>
  305. {
  306. using type = L<T1, T2, T3, T4, T5, T6, T7, T8, T9>;
  307. };
  308. template<template<class...> class L, class T1, class T2, class T3, class T4, class T5, class T6, class T7, class T8, class T9, class T10, class... T, std::size_t N>
  309. struct mp_take_c_impl<N, L<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T...>, typename std::enable_if<N >= 10>::type>
  310. {
  311. using type = mp_append<L<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10>, typename mp_take_c_impl<N-10, L<T...>>::type>;
  312. };
  313. } // namespace detail
  314. template<class L, std::size_t N> using mp_take_c = typename detail::mp_take_c_impl<N, L>::type;
  315. template<class L, class N> using mp_take = typename detail::mp_take_c_impl<std::size_t{ N::value }, L>::type;
  316. // mp_back<L>
  317. template<class L> using mp_back = mp_at_c<L, mp_size<L>::value - 1>;
  318. // mp_pop_back<L>
  319. template<class L> using mp_pop_back = mp_take_c<L, mp_size<L>::value - 1>;
  320. // mp_replace<L, V, W>
  321. namespace detail
  322. {
  323. template<class L, class V, class W> struct mp_replace_impl;
  324. template<template<class...> class L, class... T, class V, class W> struct mp_replace_impl<L<T...>, V, W>
  325. {
  326. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, <= 1800 )
  327. template<class A> struct _f { using type = mp_if<std::is_same<A, V>, W, A>; };
  328. using type = L<typename _f<T>::type...>;
  329. #else
  330. template<class A> using _f = mp_if<std::is_same<A, V>, W, A>;
  331. using type = L<_f<T>...>;
  332. #endif
  333. };
  334. } // namespace detail
  335. template<class L, class V, class W> using mp_replace = typename detail::mp_replace_impl<L, V, W>::type;
  336. // mp_replace_if<L, P, W>
  337. namespace detail
  338. {
  339. template<class L, template<class...> class P, class W> struct mp_replace_if_impl;
  340. template<template<class...> class L, class... T, template<class...> class P, class W> struct mp_replace_if_impl<L<T...>, P, W>
  341. {
  342. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, < 1920 )
  343. template<class U> struct _f { using type = mp_if<P<U>, W, U>; };
  344. using type = L<typename _f<T>::type...>;
  345. #else
  346. template<class U> using _f = mp_if<P<U>, W, U>;
  347. using type = L<_f<T>...>;
  348. #endif
  349. };
  350. } // namespace detail
  351. template<class L, template<class...> class P, class W> using mp_replace_if = typename detail::mp_replace_if_impl<L, P, W>::type;
  352. template<class L, class Q, class W> using mp_replace_if_q = mp_replace_if<L, Q::template fn, W>;
  353. // mp_copy_if<L, P>
  354. // in detail/mp_copy_if.hpp
  355. // mp_remove<L, V>
  356. namespace detail
  357. {
  358. template<class L, class V> struct mp_remove_impl;
  359. template<template<class...> class L, class... T, class V> struct mp_remove_impl<L<T...>, V>
  360. {
  361. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, < 1920 )
  362. template<class U> struct _f { using type = mp_if<std::is_same<U, V>, mp_list<>, mp_list<U>>; };
  363. using type = mp_append<L<>, typename _f<T>::type...>;
  364. #else
  365. template<class U> using _f = mp_if<std::is_same<U, V>, mp_list<>, mp_list<U>>;
  366. using type = mp_append<L<>, _f<T>...>;
  367. #endif
  368. };
  369. } // namespace detail
  370. template<class L, class V> using mp_remove = typename detail::mp_remove_impl<L, V>::type;
  371. // mp_remove_if<L, P>
  372. // in detail/mp_remove_if.hpp
  373. // mp_flatten<L, L2 = mp_clear<L>>
  374. namespace detail
  375. {
  376. template<class L2> struct mp_flatten_impl
  377. {
  378. template<class T> using fn = mp_if<mp_similar<L2, T>, T, mp_list<T>>;
  379. };
  380. } // namespace detail
  381. template<class L, class L2 = mp_clear<L>> using mp_flatten = mp_apply<mp_append, mp_push_front<mp_transform_q<detail::mp_flatten_impl<L2>, L>, mp_clear<L>>>;
  382. // mp_partition<L, P>
  383. namespace detail
  384. {
  385. template<class L, template<class...> class P> struct mp_partition_impl;
  386. template<template<class...> class L, class... T, template<class...> class P> struct mp_partition_impl<L<T...>, P>
  387. {
  388. using type = L<mp_copy_if<L<T...>, P>, mp_remove_if<L<T...>, P>>;
  389. };
  390. } // namespace detail
  391. template<class L, template<class...> class P> using mp_partition = typename detail::mp_partition_impl<L, P>::type;
  392. template<class L, class Q> using mp_partition_q = mp_partition<L, Q::template fn>;
  393. // mp_sort<L, P>
  394. namespace detail
  395. {
  396. template<class L, template<class...> class P> struct mp_sort_impl;
  397. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, <= 1800 )
  398. template<template<class...> class L, class... T, template<class...> class P> struct mp_sort_impl<L<T...>, P>
  399. {
  400. static_assert( sizeof...(T) == 0, "T... must be empty" );
  401. using type = L<>;
  402. };
  403. #else
  404. template<template<class...> class L, template<class...> class P> struct mp_sort_impl<L<>, P>
  405. {
  406. using type = L<>;
  407. };
  408. #endif
  409. template<template<class...> class L, class T1, template<class...> class P> struct mp_sort_impl<L<T1>, P>
  410. {
  411. using type = L<T1>;
  412. };
  413. template<template<class...> class L, class T1, class... T, template<class...> class P> struct mp_sort_impl<L<T1, T...>, P>
  414. {
  415. template<class U> using F = P<U, T1>;
  416. using part = mp_partition<L<T...>, F>;
  417. using S1 = typename mp_sort_impl<mp_first<part>, P>::type;
  418. using S2 = typename mp_sort_impl<mp_second<part>, P>::type;
  419. using type = mp_append<mp_push_back<S1, T1>, S2>;
  420. };
  421. } // namespace detail
  422. template<class L, template<class...> class P> using mp_sort = typename detail::mp_sort_impl<L, P>::type;
  423. template<class L, class Q> using mp_sort_q = mp_sort<L, Q::template fn>;
  424. // mp_nth_element(_c)<L, I, P>
  425. namespace detail
  426. {
  427. template<class L, std::size_t I, template<class...> class P> struct mp_nth_element_impl;
  428. template<template<class...> class L, class T1, std::size_t I, template<class...> class P> struct mp_nth_element_impl<L<T1>, I, P>
  429. {
  430. static_assert( I == 0, "mp_nth_element index out of range" );
  431. using type = T1;
  432. };
  433. template<template<class...> class L, class T1, class... T, std::size_t I, template<class...> class P> struct mp_nth_element_impl<L<T1, T...>, I, P>
  434. {
  435. static_assert( I < 1 + sizeof...(T), "mp_nth_element index out of range" );
  436. template<class U> using F = P<U, T1>;
  437. using part = mp_partition<L<T...>, F>;
  438. using L1 = mp_first<part>;
  439. static std::size_t const N1 = mp_size<L1>::value;
  440. using L2 = mp_second<part>;
  441. #if BOOST_MP11_WORKAROUND( BOOST_MP11_CUDA, >= 9000000 && BOOST_MP11_CUDA < 10000000 )
  442. struct detail
  443. {
  444. struct mp_nth_element_impl_cuda_workaround
  445. {
  446. using type = mp_cond<
  447. mp_bool<(I < N1)>, mp_nth_element_impl<L1, I, P>,
  448. mp_bool<(I == N1)>, mp_identity<T1>,
  449. mp_true, mp_nth_element_impl<L2, I - N1 - 1, P>
  450. >;
  451. };
  452. };
  453. using type = typename detail::mp_nth_element_impl_cuda_workaround::type::type;
  454. #else
  455. using type = typename mp_cond<
  456. mp_bool<(I < N1)>, mp_nth_element_impl<L1, I, P>,
  457. mp_bool<(I == N1)>, mp_identity<T1>,
  458. mp_true, mp_nth_element_impl<L2, I - N1 - 1, P>
  459. >::type;
  460. #endif
  461. };
  462. } // namespace detail
  463. template<class L, std::size_t I, template<class...> class P> using mp_nth_element_c = typename detail::mp_nth_element_impl<L, I, P>::type;
  464. template<class L, class I, template<class...> class P> using mp_nth_element = typename detail::mp_nth_element_impl<L, std::size_t{ I::value }, P>::type;
  465. template<class L, class I, class Q> using mp_nth_element_q = mp_nth_element<L, I, Q::template fn>;
  466. // mp_find<L, V>
  467. namespace detail
  468. {
  469. template<class L, class V> struct mp_find_impl;
  470. #if BOOST_MP11_CLANG && defined( BOOST_MP11_HAS_FOLD_EXPRESSIONS )
  471. struct mp_index_holder
  472. {
  473. std::size_t i_;
  474. bool f_;
  475. };
  476. constexpr inline mp_index_holder operator+( mp_index_holder const & v, bool f )
  477. {
  478. if( v.f_ )
  479. {
  480. return v;
  481. }
  482. else if( f )
  483. {
  484. return { v.i_, true };
  485. }
  486. else
  487. {
  488. return { v.i_ + 1, false };
  489. }
  490. }
  491. template<template<class...> class L, class... T, class V> struct mp_find_impl<L<T...>, V>
  492. {
  493. static constexpr mp_index_holder _v{ 0, false };
  494. using type = mp_size_t< (_v + ... + std::is_same<T, V>::value).i_ >;
  495. };
  496. #elif !defined( BOOST_MP11_NO_CONSTEXPR )
  497. template<template<class...> class L, class V> struct mp_find_impl<L<>, V>
  498. {
  499. using type = mp_size_t<0>;
  500. };
  501. #if defined( BOOST_MP11_HAS_CXX14_CONSTEXPR )
  502. constexpr std::size_t cx_find_index( bool const * first, bool const * last )
  503. {
  504. std::size_t m = 0;
  505. while( first != last && !*first )
  506. {
  507. ++m;
  508. ++first;
  509. }
  510. return m;
  511. }
  512. #else
  513. constexpr std::size_t cx_find_index( bool const * first, bool const * last )
  514. {
  515. return first == last || *first? 0: 1 + cx_find_index( first + 1, last );
  516. }
  517. #endif
  518. template<template<class...> class L, class... T, class V> struct mp_find_impl<L<T...>, V>
  519. {
  520. static constexpr bool _v[] = { std::is_same<T, V>::value... };
  521. using type = mp_size_t< cx_find_index( _v, _v + sizeof...(T) ) >;
  522. };
  523. #else
  524. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, <= 1800 )
  525. template<template<class...> class L, class... T, class V> struct mp_find_impl<L<T...>, V>
  526. {
  527. static_assert( sizeof...(T) == 0, "T... must be empty" );
  528. using type = mp_size_t<0>;
  529. };
  530. #else
  531. template<template<class...> class L, class V> struct mp_find_impl<L<>, V>
  532. {
  533. using type = mp_size_t<0>;
  534. };
  535. #endif
  536. template<template<class...> class L, class... T, class V> struct mp_find_impl<L<V, T...>, V>
  537. {
  538. using type = mp_size_t<0>;
  539. };
  540. template<template<class...> class L, class T1, class... T, class V> struct mp_find_impl<L<T1, T...>, V>
  541. {
  542. using _r = typename mp_find_impl<mp_list<T...>, V>::type;
  543. using type = mp_size_t<1 + _r::value>;
  544. };
  545. #endif
  546. } // namespace detail
  547. template<class L, class V> using mp_find = typename detail::mp_find_impl<L, V>::type;
  548. // mp_find_if<L, P>
  549. namespace detail
  550. {
  551. template<class L, template<class...> class P> struct mp_find_if_impl;
  552. #if BOOST_MP11_CLANG && defined( BOOST_MP11_HAS_FOLD_EXPRESSIONS )
  553. template<template<class...> class L, class... T, template<class...> class P> struct mp_find_if_impl<L<T...>, P>
  554. {
  555. static constexpr mp_index_holder _v{ 0, false };
  556. using type = mp_size_t< (_v + ... + P<T>::value).i_ >;
  557. };
  558. #elif !defined( BOOST_MP11_NO_CONSTEXPR )
  559. template<template<class...> class L, template<class...> class P> struct mp_find_if_impl<L<>, P>
  560. {
  561. using type = mp_size_t<0>;
  562. };
  563. template<template<class...> class L, class... T, template<class...> class P> struct mp_find_if_impl<L<T...>, P>
  564. {
  565. static constexpr bool _v[] = { P<T>::value... };
  566. using type = mp_size_t< cx_find_index( _v, _v + sizeof...(T) ) >;
  567. };
  568. #else
  569. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, <= 1800 )
  570. template<template<class...> class L, class... T, template<class...> class P> struct mp_find_if_impl<L<T...>, P>
  571. {
  572. static_assert( sizeof...(T) == 0, "T... must be empty" );
  573. using type = mp_size_t<0>;
  574. };
  575. #else
  576. template<template<class...> class L, template<class...> class P> struct mp_find_if_impl<L<>, P>
  577. {
  578. using type = mp_size_t<0>;
  579. };
  580. #endif
  581. template<class L, template<class...> class P> struct mp_find_if_impl_2
  582. {
  583. using _r = typename mp_find_if_impl<L, P>::type;
  584. using type = mp_size_t<1 + _r::value>;
  585. };
  586. template<template<class...> class L, class T1, class... T, template<class...> class P> struct mp_find_if_impl<L<T1, T...>, P>
  587. {
  588. using type = typename mp_if<P<T1>, mp_identity<mp_size_t<0>>, mp_find_if_impl_2<mp_list<T...>, P>>::type;
  589. };
  590. #endif
  591. } // namespace detail
  592. template<class L, template<class...> class P> using mp_find_if = typename detail::mp_find_if_impl<L, P>::type;
  593. template<class L, class Q> using mp_find_if_q = mp_find_if<L, Q::template fn>;
  594. // mp_reverse<L>
  595. namespace detail
  596. {
  597. template<class L> struct mp_reverse_impl;
  598. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, <= 1800 )
  599. template<template<class...> class L, class... T> struct mp_reverse_impl<L<T...>>
  600. {
  601. static_assert( sizeof...(T) == 0, "T... must be empty" );
  602. using type = L<>;
  603. };
  604. #else
  605. template<template<class...> class L> struct mp_reverse_impl<L<>>
  606. {
  607. using type = L<>;
  608. };
  609. #endif
  610. template<template<class...> class L, class T1> struct mp_reverse_impl<L<T1>>
  611. {
  612. using type = L<T1>;
  613. };
  614. template<template<class...> class L, class T1, class T2> struct mp_reverse_impl<L<T1, T2>>
  615. {
  616. using type = L<T2, T1>;
  617. };
  618. template<template<class...> class L, class T1, class T2, class T3> struct mp_reverse_impl<L<T1, T2, T3>>
  619. {
  620. using type = L<T3, T2, T1>;
  621. };
  622. template<template<class...> class L, class T1, class T2, class T3, class T4> struct mp_reverse_impl<L<T1, T2, T3, T4>>
  623. {
  624. using type = L<T4, T3, T2, T1>;
  625. };
  626. template<template<class...> class L, class T1, class T2, class T3, class T4, class T5> struct mp_reverse_impl<L<T1, T2, T3, T4, T5>>
  627. {
  628. using type = L<T5, T4, T3, T2, T1>;
  629. };
  630. template<template<class...> class L, class T1, class T2, class T3, class T4, class T5, class T6> struct mp_reverse_impl<L<T1, T2, T3, T4, T5, T6>>
  631. {
  632. using type = L<T6, T5, T4, T3, T2, T1>;
  633. };
  634. template<template<class...> class L, class T1, class T2, class T3, class T4, class T5, class T6, class T7> struct mp_reverse_impl<L<T1, T2, T3, T4, T5, T6, T7>>
  635. {
  636. using type = L<T7, T6, T5, T4, T3, T2, T1>;
  637. };
  638. template<template<class...> class L, class T1, class T2, class T3, class T4, class T5, class T6, class T7, class T8> struct mp_reverse_impl<L<T1, T2, T3, T4, T5, T6, T7, T8>>
  639. {
  640. using type = L<T8, T7, T6, T5, T4, T3, T2, T1>;
  641. };
  642. template<template<class...> class L, class T1, class T2, class T3, class T4, class T5, class T6, class T7, class T8, class T9> struct mp_reverse_impl<L<T1, T2, T3, T4, T5, T6, T7, T8, T9>>
  643. {
  644. using type = L<T9, T8, T7, T6, T5, T4, T3, T2, T1>;
  645. };
  646. template<template<class...> class L, class T1, class T2, class T3, class T4, class T5, class T6, class T7, class T8, class T9, class T10, class... T> struct mp_reverse_impl<L<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T...>>
  647. {
  648. using type = mp_push_back<typename mp_reverse_impl<L<T...>>::type, T10, T9, T8, T7, T6, T5, T4, T3, T2, T1>;
  649. };
  650. } // namespace detail
  651. template<class L> using mp_reverse = typename detail::mp_reverse_impl<L>::type;
  652. // mp_fold<L, V, F>
  653. // in detail/mp_fold.hpp
  654. // mp_reverse_fold<L, V, F>
  655. namespace detail
  656. {
  657. template<class L, class V, template<class...> class F> struct mp_reverse_fold_impl;
  658. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, <= 1800 )
  659. template<template<class...> class L, class... T, class V, template<class...> class F> struct mp_reverse_fold_impl<L<T...>, V, F>
  660. {
  661. static_assert( sizeof...(T) == 0, "T... must be empty" );
  662. using type = V;
  663. };
  664. #else
  665. template<template<class...> class L, class V, template<class...> class F> struct mp_reverse_fold_impl<L<>, V, F>
  666. {
  667. using type = V;
  668. };
  669. #endif
  670. template<template<class...> class L, class T1, class... T, class V, template<class...> class F> struct mp_reverse_fold_impl<L<T1, T...>, V, F>
  671. {
  672. using rest = typename mp_reverse_fold_impl<L<T...>, V, F>::type;
  673. using type = F<T1, rest>;
  674. };
  675. template<template<class...> class L, class T1, class T2, class T3, class T4, class T5, class T6, class T7, class T8, class T9, class T10, class... T, class V, template<class...> class F> struct mp_reverse_fold_impl<L<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T...>, V, F>
  676. {
  677. using rest = typename mp_reverse_fold_impl<L<T...>, V, F>::type;
  678. using type = F<T1, F<T2, F<T3, F<T4, F<T5, F<T6, F<T7, F<T8, F<T9, F<T10, rest> > > > > > > > > >;
  679. };
  680. } // namespace detail
  681. template<class L, class V, template<class...> class F> using mp_reverse_fold = typename detail::mp_reverse_fold_impl<L, V, F>::type;
  682. template<class L, class V, class Q> using mp_reverse_fold_q = mp_reverse_fold<L, V, Q::template fn>;
  683. // mp_unique<L>
  684. namespace detail
  685. {
  686. template<class L> struct mp_unique_impl;
  687. template<template<class...> class L, class... T> struct mp_unique_impl<L<T...>>
  688. {
  689. using type = mp_set_push_back<L<>, T...>;
  690. };
  691. } // namespace detail
  692. template<class L> using mp_unique = typename detail::mp_unique_impl<L>::type;
  693. // mp_unique_if<L, P>
  694. namespace detail
  695. {
  696. template<template<class...> class P> struct mp_unique_if_push_back
  697. {
  698. template<class...> struct impl
  699. {
  700. };
  701. template<template<class...> class L, class... Ts, class T>
  702. struct impl<L<Ts...>, T>
  703. {
  704. using type = mp_if<mp_any<P<Ts, T>...>, L<Ts...>, L<Ts..., T>>;
  705. };
  706. template<class... T> using fn = typename impl<T...>::type;
  707. };
  708. } // namespace detail
  709. template<class L, template<class...> class P>
  710. using mp_unique_if = mp_fold_q<L, mp_clear<L>, detail::mp_unique_if_push_back<P>>;
  711. template<class L, class Q> using mp_unique_if_q = mp_unique_if<L, Q::template fn>;
  712. // mp_all_of<L, P>
  713. template<class L, template<class...> class P> using mp_all_of = mp_bool< mp_count_if<L, P>::value == mp_size<L>::value >;
  714. template<class L, class Q> using mp_all_of_q = mp_all_of<L, Q::template fn>;
  715. // mp_none_of<L, P>
  716. template<class L, template<class...> class P> using mp_none_of = mp_bool< mp_count_if<L, P>::value == 0 >;
  717. template<class L, class Q> using mp_none_of_q = mp_none_of<L, Q::template fn>;
  718. // mp_any_of<L, P>
  719. template<class L, template<class...> class P> using mp_any_of = mp_bool< mp_count_if<L, P>::value != 0 >;
  720. template<class L, class Q> using mp_any_of_q = mp_any_of<L, Q::template fn>;
  721. // mp_replace_at_c<L, I, W>
  722. namespace detail
  723. {
  724. template<class L, class I, class W> struct mp_replace_at_impl
  725. {
  726. static_assert( I::value >= 0, "mp_replace_at<L, I, W>: I must not be negative" );
  727. template<class T1, class T2> using _p = std::is_same<T2, mp_size_t<I::value>>;
  728. template<class T1, class T2> using _f = W;
  729. using type = mp_transform_if<_p, _f, L, mp_iota<mp_size<L> > >;
  730. };
  731. } // namespace detail
  732. template<class L, class I, class W> using mp_replace_at = typename detail::mp_replace_at_impl<L, I, W>::type;
  733. template<class L, std::size_t I, class W> using mp_replace_at_c = typename detail::mp_replace_at_impl<L, mp_size_t<I>, W>::type;
  734. //mp_for_each<L>(f)
  735. namespace detail
  736. {
  737. template<class... T, class F> BOOST_MP11_CONSTEXPR F mp_for_each_impl( mp_list<T...>, F && f )
  738. {
  739. using A = int[sizeof...(T)];
  740. return (void)A{ ((void)f(T()), 0)... }, std::forward<F>(f);
  741. }
  742. template<class F> BOOST_MP11_CONSTEXPR F mp_for_each_impl( mp_list<>, F && f )
  743. {
  744. return std::forward<F>(f);
  745. }
  746. } // namespace detail
  747. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, >= 1900 )
  748. // msvc has a limit of 1024
  749. template<class L, class F> BOOST_MP11_CONSTEXPR mp_if_c<mp_size<L>::value <= 1024, F> mp_for_each( F && f )
  750. {
  751. return detail::mp_for_each_impl( mp_rename<L, mp_list>(), std::forward<F>(f) );
  752. }
  753. template<class L, class F> BOOST_MP11_CONSTEXPR mp_if_c<mp_size<L>::value >= 1025, F> mp_for_each( F && f )
  754. {
  755. using L2 = mp_rename<L, mp_list>;
  756. using L3 = mp_take_c<L2, 1024>;
  757. using L4 = mp_drop_c<L2, 1024>;
  758. return mp_for_each<L4>( mp_for_each<L3>( std::forward<F>(f) ) );
  759. }
  760. #else
  761. template<class L, class F> BOOST_MP11_CONSTEXPR F mp_for_each( F && f )
  762. {
  763. return detail::mp_for_each_impl( mp_rename<L, mp_list>(), std::forward<F>(f) );
  764. }
  765. #endif
  766. // mp_insert<L, I, T...>
  767. template<class L, class I, class... T> using mp_insert = mp_append<mp_take<L, I>, mp_push_front<mp_drop<L, I>, T...>>;
  768. // mp_insert_c<L, I, T...>
  769. template<class L, std::size_t I, class... T> using mp_insert_c = mp_append<mp_take_c<L, I>, mp_push_front<mp_drop_c<L, I>, T...>>;
  770. // mp_erase<L, I, J>
  771. template<class L, class I, class J> using mp_erase = mp_append<mp_take<L, I>, mp_drop<L, J>>;
  772. // mp_erase_c<L, I, J>
  773. template<class L, std::size_t I, std::size_t J> using mp_erase_c = mp_append<mp_take_c<L, I>, mp_drop_c<L, J>>;
  774. // mp_starts_with<L1, L2>
  775. // contributed by Glen Joseph Fernandes (glenjofe@gmail.com)
  776. namespace detail {
  777. template<class L1, class L2>
  778. struct mp_starts_with_impl { };
  779. template<template<class...> class L1, class... T1, template<class...> class L2,
  780. class... T2>
  781. struct mp_starts_with_impl<L1<T1...>, L2<T2...> > {
  782. template<class L>
  783. static mp_false check(L);
  784. template<class... T>
  785. static mp_true check(mp_list<T2..., T...>);
  786. using type = decltype(check(mp_list<T1...>()));
  787. };
  788. } // namespace detail
  789. template<class L1, class L2>
  790. using mp_starts_with = typename detail::mp_starts_with_impl<L1, L2>::type;
  791. // mp_rotate_left(_c)<L, N>
  792. namespace detail
  793. {
  794. // limit divisor to 1 to avoid division by 0 and give a rotation of 0 for lists containing 0 or 1 elements
  795. template<std::size_t Ln, std::size_t N> using canonical_left_rotation = mp_size_t<N % (Ln == 0? 1: Ln)>;
  796. // perform right rotation as a left rotation by inverting the number of elements to rotate
  797. template<std::size_t Ln, std::size_t N> using canonical_right_rotation = mp_size_t<Ln - N % (Ln == 0? 1: Ln)>;
  798. // avoid errors when rotating fixed-sized lists by using mp_list for the transformation
  799. template<class L, class N, class L2 = mp_rename<L, mp_list>> using mp_rotate_impl = mp_assign<L, mp_append< mp_drop<L2, N>, mp_take<L2, N> >>;
  800. } // namespace detail
  801. template<class L, std::size_t N> using mp_rotate_left_c = detail::mp_rotate_impl<L, detail::canonical_left_rotation<mp_size<L>::value, N>>;
  802. template<class L, class N> using mp_rotate_left = mp_rotate_left_c<L, std::size_t{ N::value }>;
  803. // mp_rotate_right(_c)<L, N>
  804. template<class L, std::size_t N> using mp_rotate_right_c = mp_rotate_left<L, detail::canonical_right_rotation<mp_size<L>::value, N>>;
  805. template<class L, class N> using mp_rotate_right = mp_rotate_right_c<L, std::size_t{ N::value }>;
  806. // mp_min_element<L, P>
  807. // mp_max_element<L, P>
  808. // in detail/mp_min_element.hpp
  809. // mp_power_set<L>
  810. namespace detail
  811. {
  812. template<class L> struct mp_power_set_impl;
  813. } // namespace detail
  814. template<class L> using mp_power_set = typename detail::mp_power_set_impl<L>::type;
  815. namespace detail
  816. {
  817. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, <= 1800 )
  818. template<template<class...> class L, class... T> struct mp_power_set_impl< L<T...> >
  819. {
  820. static_assert( sizeof...(T) == 0, "T... must be empty" );
  821. using type = L< L<> >;
  822. };
  823. #else
  824. template<template<class...> class L> struct mp_power_set_impl< L<> >
  825. {
  826. using type = L< L<> >;
  827. };
  828. #endif
  829. template<template<class...> class L, class T1, class... T> struct mp_power_set_impl< L<T1, T...> >
  830. {
  831. using S1 = mp_power_set< L<T...> >;
  832. template<class L2> using _f = mp_push_front<L2, T1>;
  833. using S2 = mp_transform<_f, S1>;
  834. using type = mp_append< S1, S2 >;
  835. };
  836. } // namespace detail
  837. // mp_partial_sum<L, V, F>
  838. namespace detail
  839. {
  840. template<template<class...> class F> struct mp_partial_sum_impl_f
  841. {
  842. #if BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, <= 1900 )
  843. template<class V, class T> using fn = mp_list<F<mp_first<V>, T>, mp_push_back<mp_second<V>, F<mp_first<V>, T>> >;
  844. #else
  845. template<class V, class T, class N = F<mp_first<V>, T>> using fn = mp_list<N, mp_push_back<mp_second<V>, N>>;
  846. #endif
  847. };
  848. } // namespace detail
  849. template<class L, class V, template<class...> class F> using mp_partial_sum = mp_second<mp_fold_q<L, mp_list<V, mp_clear<L>>, detail::mp_partial_sum_impl_f<F>> >;
  850. template<class L, class V, class Q> using mp_partial_sum_q = mp_partial_sum<L, V, Q::template fn>;
  851. // mp_iterate<V, F, R>
  852. namespace detail
  853. {
  854. template<class V, template<class...> class F, template<class...> class R, class N> struct mp_iterate_impl;
  855. } // namespace detail
  856. template<class V, template<class...> class F, template<class...> class R> using mp_iterate = typename detail::mp_iterate_impl<V, F, R, mp_valid<R, V>>::type;
  857. namespace detail
  858. {
  859. template<class V, template<class...> class F, template<class...> class R> struct mp_iterate_impl<V, F, R, mp_false>
  860. {
  861. template<class X> using _f = mp_list<F<X>>;
  862. using type = mp_eval_or<mp_list<>, _f, V>;
  863. };
  864. template<class V, template<class...> class F, template<class...> class R> struct mp_iterate_impl<V, F, R, mp_true>
  865. {
  866. using type = mp_push_front<mp_iterate<R<V>, F, R>, F<V>>;
  867. };
  868. } // namespace detail
  869. template<class V, class Qf, class Qr> using mp_iterate_q = mp_iterate<V, Qf::template fn, Qr::template fn>;
  870. // mp_pairwise_fold<L, F>
  871. namespace detail
  872. {
  873. template<class L, class Q> using mp_pairwise_fold_impl = mp_transform_q<Q, mp_pop_back<L>, mp_pop_front<L>>;
  874. } // namespace detail
  875. template<class L, class Q> using mp_pairwise_fold_q = mp_eval_if<mp_empty<L>, mp_clear<L>, detail::mp_pairwise_fold_impl, L, Q>;
  876. template<class L, template<class...> class F> using mp_pairwise_fold = mp_pairwise_fold_q<L, mp_quote<F>>;
  877. } // namespace mp11
  878. } // namespace boost
  879. #endif // #ifndef BOOST_MP11_ALGORITHM_HPP_INCLUDED