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 
49 namespace std _GLIBCXX_VISIBILITY(default)
50 {
51 namespace experimental
52 {
53 inline namespace fundamentals_v1
54 {
55 _GLIBCXX_BEGIN_NAMESPACE_VERSION
56 
57  // See C++14 ยง20.9.9, Function object binders
58 
59  /// Variable template for std::is_bind_expression
60  template<typename _Tp>
61  constexpr bool is_bind_expression_v = std::is_bind_expression<_Tp>::value;
62 
63  /// Variable template for std::is_placeholder
64  template<typename _Tp>
65  constexpr int is_placeholder_v = std::is_placeholder<_Tp>::value;
66 
67 #define __cpp_lib_experimental_boyer_moore_searching 201411
68 
69  // Searchers
70 
71  template<typename _ForwardIterator1, typename _BinaryPredicate = equal_to<>>
72  class default_searcher
73  {
74  public:
75  default_searcher(_ForwardIterator1 __pat_first,
76  _ForwardIterator1 __pat_last,
77  _BinaryPredicate __pred = _BinaryPredicate())
78  : _M_m(__pat_first, __pat_last, std::move(__pred))
79  { }
80 
81  template<typename _ForwardIterator2>
82  _ForwardIterator2
83  operator()(_ForwardIterator2 __first, _ForwardIterator2 __last) const
84  {
85  return std::search(__first, __last,
86  std::get<0>(_M_m), std::get<1>(_M_m),
87  std::get<2>(_M_m));
88  }
89 
90  private:
92  };
93 
94  template<typename _Key, typename _Tp, typename _Hash, typename _Pred>
95  struct __boyer_moore_map_base
96  {
97  template<typename _RAIter>
98  __boyer_moore_map_base(_RAIter __pat, size_t __patlen,
99  _Hash&& __hf, _Pred&& __pred)
100  : _M_bad_char{ __patlen, std::move(__hf), std::move(__pred) }
101  {
102  if (__patlen > 0)
103  for (__diff_type __i = 0; __i < __patlen - 1; ++__i)
104  _M_bad_char[__pat[__i]] = __patlen - 1 - __i;
105  }
106 
107  using __diff_type = _Tp;
108 
109  __diff_type
110  _M_lookup(_Key __key, __diff_type __not_found) const
111  {
112  auto __iter = _M_bad_char.find(__key);
113  if (__iter == _M_bad_char.end())
114  return __not_found;
115  return __iter->second;
116  }
117 
118  _Pred
119  _M_pred() const { return _M_bad_char.key_eq(); }
120 
122  };
123 
124  template<typename _Tp, size_t _Len, typename _Pred>
125  struct __boyer_moore_array_base
126  {
127  template<typename _RAIter, typename _Unused>
128  __boyer_moore_array_base(_RAIter __pat, size_t __patlen,
129  _Unused&&, _Pred&& __pred)
130  : _M_bad_char{ std::array<_Tp, _Len>{}, std::move(__pred) }
131  {
132  std::get<0>(_M_bad_char).fill(__patlen);
133  if (__patlen > 0)
134  for (__diff_type __i = 0; __i < __patlen - 1; ++__i)
135  {
136  auto __ch = __pat[__i];
137  using _UCh = std::make_unsigned_t<decltype(__ch)>;
138  auto __uch = static_cast<_UCh>(__ch);
139  std::get<0>(_M_bad_char)[__uch] = __patlen - 1 - __i;
140  }
141  }
142 
143  using __diff_type = _Tp;
144 
145  template<typename _Key>
146  __diff_type
147  _M_lookup(_Key __key, __diff_type __not_found) const
148  {
149  auto __ukey = static_cast<std::make_unsigned_t<_Key>>(__key);
150  if (__ukey >= _Len)
151  return __not_found;
152  return std::get<0>(_M_bad_char)[__ukey];
153  }
154 
155  const _Pred&
156  _M_pred() const { return std::get<1>(_M_bad_char); }
157 
158  std::tuple<std::array<_Tp, _Len>, _Pred> _M_bad_char;
159  };
160 
161  template<typename _Pred>
162  struct __is_std_equal_to : std::false_type { };
163 
164  template<>
165  struct __is_std_equal_to<std::equal_to<void>> : std::true_type { };
166 
167  // Use __boyer_moore_array_base when pattern consists of narrow characters
168  // and uses std::equal_to as the predicate.
169  template<typename _RAIter, typename _Hash, typename _Pred,
170  typename _Val = typename iterator_traits<_RAIter>::value_type,
171  typename _Diff = typename iterator_traits<_RAIter>::difference_type>
172  using __boyer_moore_base_t
173  = std::conditional_t<sizeof(_Val) == 1 && is_integral<_Val>::value
174  && __is_std_equal_to<_Pred>::value,
175  __boyer_moore_array_base<_Diff, 256, _Pred>,
176  __boyer_moore_map_base<_Val, _Diff, _Hash, _Pred>>;
177 
178  template<typename _RAIter, typename _Hash
180  typename _BinaryPredicate = std::equal_to<>>
181  class boyer_moore_searcher
182  : __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>
183  {
184  using _Base = __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>;
185  using typename _Base::__diff_type;
186 
187  public:
188  boyer_moore_searcher(_RAIter __pat_first, _RAIter __pat_last,
189  _Hash __hf = _Hash(),
190  _BinaryPredicate __pred = _BinaryPredicate());
191 
192  template<typename _RandomAccessIterator2>
193  _RandomAccessIterator2
194  operator()(_RandomAccessIterator2 __first,
195  _RandomAccessIterator2 __last) const;
196 
197  private:
198  bool
199  _M_is_prefix(_RAIter __word, __diff_type __len,
200  __diff_type __pos)
201  {
202  const auto& __pred = this->_M_pred();
203  __diff_type __suffixlen = __len - __pos;
204  for (__diff_type __i = 0; __i < __suffixlen; ++__i)
205  if (!__pred(__word[__i], __word[__pos + __i]))
206  return false;
207  return true;
208  }
209 
210  __diff_type
211  _M_suffix_length(_RAIter __word, __diff_type __len,
212  __diff_type __pos)
213  {
214  const auto& __pred = this->_M_pred();
215  __diff_type __i = 0;
216  while (__pred(__word[__pos - __i], __word[__len - 1 - __i])
217  && __i < __pos)
218  {
219  ++__i;
220  }
221  return __i;
222  }
223 
224  template<typename _Tp>
225  __diff_type
226  _M_bad_char_shift(_Tp __c) const
227  { return this->_M_lookup(__c, _M_pat_end - _M_pat); }
228 
229  _RAIter _M_pat;
230  _RAIter _M_pat_end;
231  std::vector<__diff_type> _M_good_suffix;
232  };
233 
234  template<typename _RAIter, typename _Hash
236  typename _BinaryPredicate = std::equal_to<>>
237  class boyer_moore_horspool_searcher
238  : __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>
239  {
240  using _Base = __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>;
241  using typename _Base::__diff_type;
242 
243  public:
244  boyer_moore_horspool_searcher(_RAIter __pat,
245  _RAIter __pat_end,
246  _Hash __hf = _Hash(),
247  _BinaryPredicate __pred
248  = _BinaryPredicate())
249  : _Base(__pat, __pat_end - __pat, std::move(__hf), std::move(__pred)),
250  _M_pat(__pat), _M_pat_end(__pat_end)
251  { }
252 
253  template<typename _RandomAccessIterator2>
254  _RandomAccessIterator2
255  operator()(_RandomAccessIterator2 __first,
256  _RandomAccessIterator2 __last) const
257  {
258  const auto& __pred = this->_M_pred();
259  auto __patlen = _M_pat_end - _M_pat;
260  if (__patlen == 0)
261  return __first;
262  auto __len = __last - __first;
263  while (__len >= __patlen)
264  {
265  for (auto __scan = __patlen - 1;
266  __pred(__first[__scan], _M_pat[__scan]); --__scan)
267  if (__scan == 0)
268  return __first;
269  auto __shift = _M_bad_char_shift(__first[__patlen - 1]);
270  __len -= __shift;
271  __first += __shift;
272  }
273  return __last;
274  }
275 
276  private:
277  template<typename _Tp>
278  __diff_type
279  _M_bad_char_shift(_Tp __c) const
280  { return this->_M_lookup(__c, _M_pat_end - _M_pat); }
281 
282  _RAIter _M_pat;
283  _RAIter _M_pat_end;
284  };
285 
286  /// Generator function for default_searcher
287  template<typename _ForwardIterator,
288  typename _BinaryPredicate = std::equal_to<>>
289  inline default_searcher<_ForwardIterator, _BinaryPredicate>
290  make_default_searcher(_ForwardIterator __pat_first,
291  _ForwardIterator __pat_last,
292  _BinaryPredicate __pred = _BinaryPredicate())
293  { return { __pat_first, __pat_last, __pred }; }
294 
295  /// Generator function for boyer_moore_searcher
296  template<typename _RAIter, typename _Hash
298  typename _BinaryPredicate = equal_to<>>
299  inline boyer_moore_searcher<_RAIter, _Hash, _BinaryPredicate>
300  make_boyer_moore_searcher(_RAIter __pat_first, _RAIter __pat_last,
301  _Hash __hf = _Hash(),
302  _BinaryPredicate __pred = _BinaryPredicate())
303  { return { __pat_first, __pat_last, std::move(__hf), std::move(__pred) }; }
304 
305  /// Generator function for boyer_moore_horspool_searcher
306  template<typename _RAIter, typename _Hash
308  typename _BinaryPredicate = equal_to<>>
309  inline boyer_moore_horspool_searcher<_RAIter, _Hash, _BinaryPredicate>
310  make_boyer_moore_horspool_searcher(_RAIter __pat_first, _RAIter __pat_last,
311  _Hash __hf = _Hash(),
312  _BinaryPredicate __pred
313  = _BinaryPredicate())
314  { return { __pat_first, __pat_last, std::move(__hf), std::move(__pred) }; }
315 
316  template<typename _RAIter, typename _Hash, typename _BinaryPredicate>
317  boyer_moore_searcher<_RAIter, _Hash, _BinaryPredicate>::
318  boyer_moore_searcher(_RAIter __pat, _RAIter __pat_end,
319  _Hash __hf, _BinaryPredicate __pred)
320  : _Base(__pat, __pat_end - __pat, std::move(__hf), std::move(__pred)),
321  _M_pat(__pat), _M_pat_end(__pat_end), _M_good_suffix(__pat_end - __pat)
322  {
323  auto __patlen = __pat_end - __pat;
324  if (__patlen == 0)
325  return;
326  __diff_type __last_prefix = __patlen - 1;
327  for (__diff_type __p = __patlen - 1; __p >= 0; --__p)
328  {
329  if (_M_is_prefix(__pat, __patlen, __p + 1))
330  __last_prefix = __p + 1;
331  _M_good_suffix[__p] = __last_prefix + (__patlen - 1 - __p);
332  }
333  for (__diff_type __p = 0; __p < __patlen - 1; ++__p)
334  {
335  auto __slen = _M_suffix_length(__pat, __patlen, __p);
336  auto __pos = __patlen - 1 - __slen;
337  if (!__pred(__pat[__p - __slen], __pat[__pos]))
338  _M_good_suffix[__pos] = __patlen - 1 - __p + __slen;
339  }
340  }
341 
342  template<typename _RAIter, typename _Hash, typename _BinaryPredicate>
343  template<typename _RandomAccessIterator2>
344  _RandomAccessIterator2
345  boyer_moore_searcher<_RAIter, _Hash, _BinaryPredicate>::
346  operator()(_RandomAccessIterator2 __first,
347  _RandomAccessIterator2 __last) const
348  {
349  auto __patlen = _M_pat_end - _M_pat;
350  if (__patlen == 0)
351  return __first;
352  const auto& __pred = this->_M_pred();
353  __diff_type __i = __patlen - 1;
354  auto __stringlen = __last - __first;
355  while (__i < __stringlen)
356  {
357  __diff_type __j = __patlen - 1;
358  while (__j >= 0 && __pred(__first[__i], _M_pat[__j]))
359  {
360  --__i;
361  --__j;
362  }
363  if (__j < 0)
364  return __first + __i + 1;
365  __i += std::max(_M_bad_char_shift(__first[__i]),
366  _M_good_suffix[__j]);
367  }
368  return __last;
369  }
370 
371 _GLIBCXX_END_NAMESPACE_VERSION
372 } // namespace fundamentals_v1
373 
374 inline namespace fundamentals_v2
375 {
376 _GLIBCXX_BEGIN_NAMESPACE_VERSION
377 
378 #define __cpp_lib_experimental_not_fn 201406
379 
380  /// Generalized negator.
381  template<typename _Fn>
382  class _Not_fn
383  {
384  _Fn _M_fn;
385 
386  public:
387  template<typename _Fn2>
388  explicit
389  _Not_fn(_Fn2&& __fn) : _M_fn(std::forward<_Fn2>(__fn)) { }
390 
391  _Not_fn(const _Not_fn& __fn) = default;
392  _Not_fn(_Not_fn&& __fn) = default;
393  _Not_fn& operator=(const _Not_fn& __fn) = default;
394  _Not_fn& operator=(_Not_fn&& __fn) = default;
395  ~_Not_fn() = default;
396 
397  template<typename... _Args>
398  auto
399  operator()(_Args&&... __args)
400  noexcept(noexcept(!_M_fn(std::forward<_Args>(__args)...)))
401  -> decltype(!_M_fn(std::forward<_Args>(__args)...))
402  { return !_M_fn(std::forward<_Args>(__args)...); }
403 
404  template<typename... _Args>
405  auto
406  operator()(_Args&&... __args) const
407  noexcept(noexcept(!_M_fn(std::forward<_Args>(__args)...)))
408  -> decltype(!_M_fn(std::forward<_Args>(__args)...))
409  { return !_M_fn(std::forward<_Args>(__args)...); }
410 
411  template<typename... _Args>
412  auto
413  operator()(_Args&&... __args) volatile
414  noexcept(noexcept(!_M_fn(std::forward<_Args>(__args)...)))
415  -> decltype(!_M_fn(std::forward<_Args>(__args)...))
416  { return !_M_fn(std::forward<_Args>(__args)...); }
417 
418  template<typename... _Args>
419  auto
420  operator()(_Args&&... __args) const volatile
421  noexcept(noexcept(!_M_fn(std::forward<_Args>(__args)...)))
422  -> decltype(!_M_fn(std::forward<_Args>(__args)...))
423  { return !_M_fn(std::forward<_Args>(__args)...); }
424  };
425 
426  /// [func.not_fn] Function template not_fn
427  template<typename _Fn>
428  inline auto
429  not_fn(_Fn&& __fn)
430  noexcept(std::is_nothrow_constructible<std::decay_t<_Fn>, _Fn&&>::value)
431  {
432  using __maybe_type = _Maybe_wrap_member_pointer<std::decay_t<_Fn>>;
433  return _Not_fn<typename __maybe_type::type>{std::forward<_Fn>(__fn)};
434  }
435 
436 _GLIBCXX_END_NAMESPACE_VERSION
437 } // namespace fundamentals_v2
438 } // namespace experimental
439 } // namespace std
440 
441 #endif // C++14
442 
443 #endif // _GLIBCXX_EXPERIMENTAL_FUNCTIONAL
_GLIBCXX14_CONSTEXPR const _Tp & max(const _Tp &, const _Tp &)
This does what you think it does.
Definition: stl_algobase.h:219
Primary class template hash.
Definition: system_error:134
A standard container for storing a fixed size sequence of elements.
Definition: array:90
Determines if the given type _Tp is a function object that should be treated as a subexpression when ...
Definition: functional:670
One of the comparison functors.
Definition: stl_function.h:332
_ForwardIterator1 search(_ForwardIterator1 __first1, _ForwardIterator1 __last1, _ForwardIterator2 __first2, _ForwardIterator2 __last2, _BinaryPredicate __predicate)
Search a sequence for a matching sub-sequence using a predicate.
Definition: stl_algo.h:4064
integral_constant
Definition: type_traits:69
Determines if the given type _Tp is a placeholder in a bind() expression and, if so, which placeholder it is.
Definition: functional:681