libstdc++
experimental/functional
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1// <experimental/functional> -*- C++ -*-
2
3// Copyright (C) 2014-2016 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/** @file experimental/functional
26 * This is a TS C++ Library header.
27 */
28
29#ifndef _GLIBCXX_EXPERIMENTAL_FUNCTIONAL
30#define _GLIBCXX_EXPERIMENTAL_FUNCTIONAL 1
31
32#pragma GCC system_header
33
34#if __cplusplus <= 201103L
35# include <bits/c++14_warning.h>
36#else
37
38#include <functional>
39#include <tuple>
40#include <iterator>
41#include <unordered_map>
42#include <vector>
43#include <array>
44#include <bits/stl_algo.h>
45#ifdef _GLIBCXX_PARALLEL
46# include <parallel/algorithm> // For std::__parallel::search
47#endif
48#include <experimental/bits/lfts_config.h>
49
50namespace std _GLIBCXX_VISIBILITY(default)
51{
52namespace experimental
53{
54inline namespace fundamentals_v1
55{
56_GLIBCXX_BEGIN_NAMESPACE_VERSION
57
58 // See C++14 ยง20.9.9, Function object binders
59
60 /// Variable template for std::is_bind_expression
61 template<typename _Tp>
62 constexpr bool is_bind_expression_v = std::is_bind_expression<_Tp>::value;
63
64 /// Variable template for std::is_placeholder
65 template<typename _Tp>
66 constexpr int is_placeholder_v = std::is_placeholder<_Tp>::value;
67
68#define __cpp_lib_experimental_boyer_moore_searching 201411
69
70 // Searchers
71
72 template<typename _ForwardIterator1, typename _BinaryPredicate = equal_to<>>
73 class default_searcher
74 {
75 public:
76 default_searcher(_ForwardIterator1 __pat_first,
77 _ForwardIterator1 __pat_last,
78 _BinaryPredicate __pred = _BinaryPredicate())
79 : _M_m(__pat_first, __pat_last, std::move(__pred))
80 { }
81
82 template<typename _ForwardIterator2>
83 _ForwardIterator2
84 operator()(_ForwardIterator2 __first, _ForwardIterator2 __last) const
85 {
86 return std::search(__first, __last,
87 std::get<0>(_M_m), std::get<1>(_M_m),
88 std::get<2>(_M_m));
89 }
90
91 private:
92 std::tuple<_ForwardIterator1, _ForwardIterator1, _BinaryPredicate> _M_m;
93 };
94
95 template<typename _Key, typename _Tp, typename _Hash, typename _Pred>
96 struct __boyer_moore_map_base
97 {
98 template<typename _RAIter>
99 __boyer_moore_map_base(_RAIter __pat, size_t __patlen,
100 _Hash&& __hf, _Pred&& __pred)
101 : _M_bad_char{ __patlen, std::move(__hf), std::move(__pred) }
102 {
103 if (__patlen > 0)
104 for (__diff_type __i = 0; __i < __patlen - 1; ++__i)
105 _M_bad_char[__pat[__i]] = __patlen - 1 - __i;
106 }
107
108 using __diff_type = _Tp;
109
110 __diff_type
111 _M_lookup(_Key __key, __diff_type __not_found) const
112 {
113 auto __iter = _M_bad_char.find(__key);
114 if (__iter == _M_bad_char.end())
115 return __not_found;
116 return __iter->second;
117 }
118
119 _Pred
120 _M_pred() const { return _M_bad_char.key_eq(); }
121
122 _GLIBCXX_STD_C::unordered_map<_Key, _Tp, _Hash, _Pred> _M_bad_char;
123 };
124
125 template<typename _Tp, size_t _Len, typename _Pred>
126 struct __boyer_moore_array_base
127 {
128 template<typename _RAIter, typename _Unused>
129 __boyer_moore_array_base(_RAIter __pat, size_t __patlen,
130 _Unused&&, _Pred&& __pred)
131 : _M_bad_char{ _GLIBCXX_STD_C::array<_Tp, _Len>{}, std::move(__pred) }
132 {
133 std::get<0>(_M_bad_char).fill(__patlen);
134 if (__patlen > 0)
135 for (__diff_type __i = 0; __i < __patlen - 1; ++__i)
136 {
137 auto __ch = __pat[__i];
138 using _UCh = std::make_unsigned_t<decltype(__ch)>;
139 auto __uch = static_cast<_UCh>(__ch);
140 std::get<0>(_M_bad_char)[__uch] = __patlen - 1 - __i;
141 }
142 }
143
144 using __diff_type = _Tp;
145
146 template<typename _Key>
147 __diff_type
148 _M_lookup(_Key __key, __diff_type __not_found) const
149 {
150 auto __ukey = static_cast<std::make_unsigned_t<_Key>>(__key);
151 if (__ukey >= _Len)
152 return __not_found;
153 return std::get<0>(_M_bad_char)[__ukey];
154 }
155
156 const _Pred&
157 _M_pred() const { return std::get<1>(_M_bad_char); }
158
159 std::tuple<_GLIBCXX_STD_C::array<_Tp, _Len>, _Pred> _M_bad_char;
160 };
161
162 template<typename _Pred>
163 struct __is_std_equal_to : std::false_type { };
164
165 template<>
166 struct __is_std_equal_to<std::equal_to<void>> : std::true_type { };
167
168 // Use __boyer_moore_array_base when pattern consists of narrow characters
169 // and uses std::equal_to as the predicate.
170 template<typename _RAIter, typename _Hash, typename _Pred,
171 typename _Val = typename iterator_traits<_RAIter>::value_type,
172 typename _Diff = typename iterator_traits<_RAIter>::difference_type>
173 using __boyer_moore_base_t
174 = std::conditional_t<sizeof(_Val) == 1 && is_integral<_Val>::value
175 && __is_std_equal_to<_Pred>::value,
176 __boyer_moore_array_base<_Diff, 256, _Pred>,
177 __boyer_moore_map_base<_Val, _Diff, _Hash, _Pred>>;
178
179 template<typename _RAIter, typename _Hash
180 = std::hash<typename std::iterator_traits<_RAIter>::value_type>,
181 typename _BinaryPredicate = std::equal_to<>>
182 class boyer_moore_searcher
183 : __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>
184 {
185 using _Base = __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>;
186 using typename _Base::__diff_type;
187
188 public:
189 boyer_moore_searcher(_RAIter __pat_first, _RAIter __pat_last,
190 _Hash __hf = _Hash(),
191 _BinaryPredicate __pred = _BinaryPredicate());
192
193 template<typename _RandomAccessIterator2>
194 _RandomAccessIterator2
195 operator()(_RandomAccessIterator2 __first,
196 _RandomAccessIterator2 __last) const;
197
198 private:
199 bool
200 _M_is_prefix(_RAIter __word, __diff_type __len,
201 __diff_type __pos)
202 {
203 const auto& __pred = this->_M_pred();
204 __diff_type __suffixlen = __len - __pos;
205 for (__diff_type __i = 0; __i < __suffixlen; ++__i)
206 if (!__pred(__word[__i], __word[__pos + __i]))
207 return false;
208 return true;
209 }
210
211 __diff_type
212 _M_suffix_length(_RAIter __word, __diff_type __len,
213 __diff_type __pos)
214 {
215 const auto& __pred = this->_M_pred();
216 __diff_type __i = 0;
217 while (__pred(__word[__pos - __i], __word[__len - 1 - __i])
218 && __i < __pos)
219 {
220 ++__i;
221 }
222 return __i;
223 }
224
225 template<typename _Tp>
226 __diff_type
227 _M_bad_char_shift(_Tp __c) const
228 { return this->_M_lookup(__c, _M_pat_end - _M_pat); }
229
230 _RAIter _M_pat;
231 _RAIter _M_pat_end;
232 _GLIBCXX_STD_C::vector<__diff_type> _M_good_suffix;
233 };
234
235 template<typename _RAIter, typename _Hash
236 = std::hash<typename std::iterator_traits<_RAIter>::value_type>,
237 typename _BinaryPredicate = std::equal_to<>>
238 class boyer_moore_horspool_searcher
239 : __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>
240 {
241 using _Base = __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>;
242 using typename _Base::__diff_type;
243
244 public:
245 boyer_moore_horspool_searcher(_RAIter __pat,
246 _RAIter __pat_end,
247 _Hash __hf = _Hash(),
248 _BinaryPredicate __pred
249 = _BinaryPredicate())
250 : _Base(__pat, __pat_end - __pat, std::move(__hf), std::move(__pred)),
251 _M_pat(__pat), _M_pat_end(__pat_end)
252 { }
253
254 template<typename _RandomAccessIterator2>
255 _RandomAccessIterator2
256 operator()(_RandomAccessIterator2 __first,
257 _RandomAccessIterator2 __last) const
258 {
259 const auto& __pred = this->_M_pred();
260 auto __patlen = _M_pat_end - _M_pat;
261 if (__patlen == 0)
262 return __first;
263 auto __len = __last - __first;
264 while (__len >= __patlen)
265 {
266 for (auto __scan = __patlen - 1;
267 __pred(__first[__scan], _M_pat[__scan]); --__scan)
268 if (__scan == 0)
269 return __first;
270 auto __shift = _M_bad_char_shift(__first[__patlen - 1]);
271 __len -= __shift;
272 __first += __shift;
273 }
274 return __last;
275 }
276
277 private:
278 template<typename _Tp>
279 __diff_type
280 _M_bad_char_shift(_Tp __c) const
281 { return this->_M_lookup(__c, _M_pat_end - _M_pat); }
282
283 _RAIter _M_pat;
284 _RAIter _M_pat_end;
285 };
286
287 /// Generator function for default_searcher
288 template<typename _ForwardIterator,
289 typename _BinaryPredicate = std::equal_to<>>
290 inline default_searcher<_ForwardIterator, _BinaryPredicate>
291 make_default_searcher(_ForwardIterator __pat_first,
292 _ForwardIterator __pat_last,
293 _BinaryPredicate __pred = _BinaryPredicate())
294 { return { __pat_first, __pat_last, __pred }; }
295
296 /// Generator function for boyer_moore_searcher
297 template<typename _RAIter, typename _Hash
298 = std::hash<typename std::iterator_traits<_RAIter>::value_type>,
299 typename _BinaryPredicate = equal_to<>>
300 inline boyer_moore_searcher<_RAIter, _Hash, _BinaryPredicate>
301 make_boyer_moore_searcher(_RAIter __pat_first, _RAIter __pat_last,
302 _Hash __hf = _Hash(),
303 _BinaryPredicate __pred = _BinaryPredicate())
304 { return { __pat_first, __pat_last, std::move(__hf), std::move(__pred) }; }
305
306 /// Generator function for boyer_moore_horspool_searcher
307 template<typename _RAIter, typename _Hash
308 = std::hash<typename std::iterator_traits<_RAIter>::value_type>,
309 typename _BinaryPredicate = equal_to<>>
310 inline boyer_moore_horspool_searcher<_RAIter, _Hash, _BinaryPredicate>
311 make_boyer_moore_horspool_searcher(_RAIter __pat_first, _RAIter __pat_last,
312 _Hash __hf = _Hash(),
313 _BinaryPredicate __pred
314 = _BinaryPredicate())
315 { return { __pat_first, __pat_last, std::move(__hf), std::move(__pred) }; }
316
317 template<typename _RAIter, typename _Hash, typename _BinaryPredicate>
318 boyer_moore_searcher<_RAIter, _Hash, _BinaryPredicate>::
319 boyer_moore_searcher(_RAIter __pat, _RAIter __pat_end,
320 _Hash __hf, _BinaryPredicate __pred)
321 : _Base(__pat, __pat_end - __pat, std::move(__hf), std::move(__pred)),
322 _M_pat(__pat), _M_pat_end(__pat_end), _M_good_suffix(__pat_end - __pat)
323 {
324 auto __patlen = __pat_end - __pat;
325 if (__patlen == 0)
326 return;
327 __diff_type __last_prefix = __patlen - 1;
328 for (__diff_type __p = __patlen - 1; __p >= 0; --__p)
329 {
330 if (_M_is_prefix(__pat, __patlen, __p + 1))
331 __last_prefix = __p + 1;
332 _M_good_suffix[__p] = __last_prefix + (__patlen - 1 - __p);
333 }
334 for (__diff_type __p = 0; __p < __patlen - 1; ++__p)
335 {
336 auto __slen = _M_suffix_length(__pat, __patlen, __p);
337 auto __pos = __patlen - 1 - __slen;
338 if (!__pred(__pat[__p - __slen], __pat[__pos]))
339 _M_good_suffix[__pos] = __patlen - 1 - __p + __slen;
340 }
341 }
342
343 template<typename _RAIter, typename _Hash, typename _BinaryPredicate>
344 template<typename _RandomAccessIterator2>
345 _RandomAccessIterator2
346 boyer_moore_searcher<_RAIter, _Hash, _BinaryPredicate>::
347 operator()(_RandomAccessIterator2 __first,
348 _RandomAccessIterator2 __last) const
349 {
350 auto __patlen = _M_pat_end - _M_pat;
351 if (__patlen == 0)
352 return __first;
353 const auto& __pred = this->_M_pred();
354 __diff_type __i = __patlen - 1;
355 auto __stringlen = __last - __first;
356 while (__i < __stringlen)
357 {
358 __diff_type __j = __patlen - 1;
359 while (__j >= 0 && __pred(__first[__i], _M_pat[__j]))
360 {
361 --__i;
362 --__j;
363 }
364 if (__j < 0)
365 return __first + __i + 1;
366 __i += std::max(_M_bad_char_shift(__first[__i]),
367 _M_good_suffix[__j]);
368 }
369 return __last;
370 }
371
372_GLIBCXX_END_NAMESPACE_VERSION
373} // namespace fundamentals_v1
374
375inline namespace fundamentals_v2
376{
377_GLIBCXX_BEGIN_NAMESPACE_VERSION
378
379#define __cpp_lib_experimental_not_fn 201406
380
381 /// Generalized negator.
382 template<typename _Fn>
383 class _Not_fn
384 {
385 _Fn _M_fn;
386
387 public:
388 template<typename _Fn2>
389 explicit
390 _Not_fn(_Fn2&& __fn, int) : _M_fn(std::forward<_Fn2>(__fn)) { }
391
392 _Not_fn(const _Not_fn& __fn) = default;
393 _Not_fn(_Not_fn&& __fn) = default;
394 _Not_fn& operator=(const _Not_fn& __fn) = default;
395 _Not_fn& operator=(_Not_fn&& __fn) = default;
396 ~_Not_fn() = default;
397
398 template<typename... _Args>
399 auto
400 operator()(_Args&&... __args)
401 noexcept(noexcept(!_M_fn(std::forward<_Args>(__args)...)))
402 -> decltype(!_M_fn(std::forward<_Args>(__args)...))
403 { return !_M_fn(std::forward<_Args>(__args)...); }
404
405 template<typename... _Args>
406 auto
407 operator()(_Args&&... __args) const
408 noexcept(noexcept(!_M_fn(std::forward<_Args>(__args)...)))
409 -> decltype(!_M_fn(std::forward<_Args>(__args)...))
410 { return !_M_fn(std::forward<_Args>(__args)...); }
411
412 template<typename... _Args>
413 auto
414 operator()(_Args&&... __args) volatile
415 noexcept(noexcept(!_M_fn(std::forward<_Args>(__args)...)))
416 -> decltype(!_M_fn(std::forward<_Args>(__args)...))
417 { return !_M_fn(std::forward<_Args>(__args)...); }
418
419 template<typename... _Args>
420 auto
421 operator()(_Args&&... __args) const volatile
422 noexcept(noexcept(!_M_fn(std::forward<_Args>(__args)...)))
423 -> decltype(!_M_fn(std::forward<_Args>(__args)...))
424 { return !_M_fn(std::forward<_Args>(__args)...); }
425 };
426
427 /// [func.not_fn] Function template not_fn
428 template<typename _Fn>
429 inline auto
430 not_fn(_Fn&& __fn)
431 noexcept(std::is_nothrow_constructible<std::decay_t<_Fn>, _Fn&&>::value)
432 {
433 using __maybe_type = _Maybe_wrap_member_pointer<std::decay_t<_Fn>>;
434 return _Not_fn<typename __maybe_type::type>{std::forward<_Fn>(__fn), 0};
435 }
436
437_GLIBCXX_END_NAMESPACE_VERSION
438} // namespace fundamentals_v2
439} // namespace experimental
440} // namespace std
441
442#endif // C++14
443
444#endif // _GLIBCXX_EXPERIMENTAL_FUNCTIONAL