libstdc++
typelist.h
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1 // -*- C++ -*-
2 
3 // Copyright (C) 2005-2017 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 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
26 
27 // Permission to use, copy, modify, sell, and distribute this software
28 // is hereby granted without fee, provided that the above copyright
29 // notice appears in all copies, and that both that copyright notice and
30 // this permission notice appear in supporting documentation. None of
31 // the above authors, nor IBM Haifa Research Laboratories, make any
32 // representation about the suitability of this software for any
33 // purpose. It is provided "as is" without express or implied warranty.
34 
35 /**
36  * @file ext/typelist.h
37  * This file is a GNU extension to the Standard C++ Library.
38  *
39  * Contains typelist_chain definitions.
40  * Typelists are an idea by Andrei Alexandrescu.
41  */
42 
43 #ifndef _TYPELIST_H
44 #define _TYPELIST_H 1
45 
46 #include <ext/type_traits.h>
47 
48 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
49 {
50 _GLIBCXX_BEGIN_NAMESPACE_VERSION
51 
52 /** @namespace __gnu_cxx::typelist
53  * @brief GNU typelist extensions for public compile-time use.
54 */
55 namespace typelist
56 {
57  struct null_type { };
58 
59  template<typename Root>
60  struct node
61  {
62  typedef Root root;
63  };
64 
65  // Forward declarations of functors.
66  template<typename Hd, typename Typelist>
67  struct chain
68  {
69  typedef Hd head;
70  typedef Typelist tail;
71  };
72 
73  // Apply all typelist types to unary functor.
74  template<typename Fn, typename Typelist>
75  void
76  apply(Fn&, Typelist);
77 
78  /// Apply all typelist types to generator functor.
79  template<typename Gn, typename Typelist>
80  void
81  apply_generator(Gn&, Typelist);
82 
83  // Apply all typelist types and values to generator functor.
84  template<typename Gn, typename TypelistT, typename TypelistV>
85  void
86  apply_generator(Gn&, TypelistT, TypelistV);
87 
88  template<typename Typelist0, typename Typelist1>
89  struct append;
90 
91  template<typename Typelist_Typelist>
92  struct append_typelist;
93 
94  template<typename Typelist, typename T>
95  struct contains;
96 
97  template<typename Typelist, template<typename T> class Pred>
98  struct filter;
99 
100  template<typename Typelist, int i>
101  struct at_index;
102 
103  template<typename Typelist, template<typename T> class Transform>
104  struct transform;
105 
106  template<typename Typelist_Typelist>
107  struct flatten;
108 
109  template<typename Typelist>
110  struct from_first;
111 
112  template<typename T1>
113  struct create1;
114 
115  template<typename T1, typename T2>
116  struct create2;
117 
118  template<typename T1, typename T2, typename T3>
119  struct create3;
120 
121  template<typename T1, typename T2, typename T3, typename T4>
122  struct create4;
123 
124  template<typename T1, typename T2, typename T3, typename T4, typename T5>
125  struct create5;
126 
127  template<typename T1, typename T2, typename T3,
128  typename T4, typename T5, typename T6>
129  struct create6;
130 } // namespace typelist
131 
132 _GLIBCXX_END_NAMESPACE_VERSION
133 } // namespace
134 
135 
136 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
137 {
138 _GLIBCXX_BEGIN_NAMESPACE_VERSION
139 
140 namespace typelist
141 {
142 namespace detail
143 {
144  template<typename Fn, typename Typelist_Chain>
145  struct apply_;
146 
147  template<typename Fn, typename Hd, typename Tl>
148  struct apply_<Fn, chain<Hd, Tl> >
149  {
150  void
151  operator()(Fn& f)
152  {
153  f.operator()(Hd());
154  apply_<Fn, Tl> next;
155  next(f);
156  }
157  };
158 
159  template<typename Fn>
160  struct apply_<Fn, null_type>
161  {
162  void
163  operator()(Fn&) { }
164  };
165 
166  template<typename Gn, typename Typelist_Chain>
167  struct apply_generator1_;
168 
169  template<typename Gn, typename Hd, typename Tl>
170  struct apply_generator1_<Gn, chain<Hd, Tl> >
171  {
172  void
173  operator()(Gn& g)
174  {
175  g.template operator()<Hd>();
176  apply_generator1_<Gn, Tl> next;
177  next(g);
178  }
179  };
180 
181  template<typename Gn>
182  struct apply_generator1_<Gn, null_type>
183  {
184  void
185  operator()(Gn&) { }
186  };
187 
188  template<typename Gn, typename TypelistT_Chain, typename TypelistV_Chain>
189  struct apply_generator2_;
190 
191  template<typename Gn, typename Hd1, typename TlT, typename Hd2, typename TlV>
192  struct apply_generator2_<Gn, chain<Hd1, TlT>, chain<Hd2, TlV> >
193  {
194  void
195  operator()(Gn& g)
196  {
197  g.template operator()<Hd1, Hd2>();
198  apply_generator2_<Gn, TlT, TlV> next;
199  next(g);
200  }
201  };
202 
203  template<typename Gn>
204  struct apply_generator2_<Gn, null_type, null_type>
205  {
206  void
207  operator()(Gn&) { }
208  };
209 
210  template<typename Typelist_Chain0, typename Typelist_Chain1>
211  struct append_;
212 
213  template<typename Hd, typename Tl, typename Typelist_Chain>
214  struct append_<chain<Hd, Tl>, Typelist_Chain>
215  {
216  private:
217  typedef append_<Tl, Typelist_Chain> append_type;
218 
219  public:
220  typedef chain<Hd, typename append_type::type> type;
221  };
222 
223  template<typename Typelist_Chain>
224  struct append_<null_type, Typelist_Chain>
225  {
226  typedef Typelist_Chain type;
227  };
228 
229  template<typename Typelist_Chain>
230  struct append_<Typelist_Chain, null_type>
231  {
232  typedef Typelist_Chain type;
233  };
234 
235  template<>
236  struct append_<null_type, null_type>
237  {
238  typedef null_type type;
239  };
240 
241  template<typename Typelist_Typelist_Chain>
242  struct append_typelist_;
243 
244  template<typename Hd>
245  struct append_typelist_<chain<Hd, null_type> >
246  {
247  typedef chain<Hd, null_type> type;
248  };
249 
250  template<typename Hd, typename Tl>
251  struct append_typelist_<chain< Hd, Tl> >
252  {
253  private:
254  typedef typename append_typelist_<Tl>::type rest_type;
255 
256  public:
257  typedef typename append<Hd, node<rest_type> >::type::root type;
258  };
259 
260  template<typename Typelist_Chain, typename T>
261  struct contains_;
262 
263  template<typename T>
264  struct contains_<null_type, T>
265  {
266  enum
267  {
268  value = false
269  };
270  };
271 
272  template<typename Hd, typename Tl, typename T>
273  struct contains_<chain<Hd, Tl>, T>
274  {
275  enum
276  {
277  value = contains_<Tl, T>::value
278  };
279  };
280 
281  template<typename Tl, typename T>
282  struct contains_<chain<T, Tl>, T>
283  {
284  enum
285  {
286  value = true
287  };
288  };
289 
290  template<typename Typelist_Chain, template<typename T> class Pred>
291  struct chain_filter_;
292 
293  template<template<typename T> class Pred>
294  struct chain_filter_<null_type, Pred>
295  {
296  typedef null_type type;
297  };
298 
299  template<typename Hd, typename Tl, template<typename T> class Pred>
300  struct chain_filter_<chain<Hd, Tl>, Pred>
301  {
302  private:
303  enum
304  {
305  include_hd = Pred<Hd>::value
306  };
307 
308  typedef typename chain_filter_<Tl, Pred>::type rest_type;
309  typedef chain<Hd, rest_type> chain_type;
310 
311  public:
312  typedef typename __conditional_type<include_hd, chain_type, rest_type>::__type type;
313  };
314 
315  template<typename Typelist_Chain, int i>
316  struct chain_at_index_;
317 
318  template<typename Hd, typename Tl>
319  struct chain_at_index_<chain<Hd, Tl>, 0>
320  {
321  typedef Hd type;
322  };
323 
324  template<typename Hd, typename Tl, int i>
325  struct chain_at_index_<chain<Hd, Tl>, i>
326  {
327  typedef typename chain_at_index_<Tl, i - 1>::type type;
328  };
329 
330  template<class Typelist_Chain, template<typename T> class Transform>
331  struct chain_transform_;
332 
333  template<template<typename T> class Transform>
334  struct chain_transform_<null_type, Transform>
335  {
336  typedef null_type type;
337  };
338 
339  template<class Hd, class Tl, template<typename T> class Transform>
340  struct chain_transform_<chain<Hd, Tl>, Transform>
341  {
342  private:
343  typedef typename chain_transform_<Tl, Transform>::type rest_type;
344  typedef typename Transform<Hd>::type transform_type;
345 
346  public:
347  typedef chain<transform_type, rest_type> type;
348  };
349 
350  template<typename Typelist_Typelist_Chain>
351  struct chain_flatten_;
352 
353  template<typename Hd_Tl>
354  struct chain_flatten_<chain<Hd_Tl, null_type> >
355  {
356  typedef typename Hd_Tl::root type;
357  };
358 
359  template<typename Hd_Typelist, class Tl_Typelist>
360  struct chain_flatten_<chain<Hd_Typelist, Tl_Typelist> >
361  {
362  private:
363  typedef typename chain_flatten_<Tl_Typelist>::type rest_type;
364  typedef append<Hd_Typelist, node<rest_type> > append_type;
365  public:
366  typedef typename append_type::type::root type;
367  };
368 } // namespace detail
369 } // namespace typelist
370 
371 _GLIBCXX_END_NAMESPACE_VERSION
372 } // namespace
373 
374 #define _GLIBCXX_TYPELIST_CHAIN1(X0) __gnu_cxx::typelist::chain<X0, __gnu_cxx::typelist::null_type>
375 #define _GLIBCXX_TYPELIST_CHAIN2(X0, X1) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN1(X1) >
376 #define _GLIBCXX_TYPELIST_CHAIN3(X0, X1, X2) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN2(X1, X2) >
377 #define _GLIBCXX_TYPELIST_CHAIN4(X0, X1, X2, X3) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN3(X1, X2, X3) >
378 #define _GLIBCXX_TYPELIST_CHAIN5(X0, X1, X2, X3, X4) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN4(X1, X2, X3, X4) >
379 #define _GLIBCXX_TYPELIST_CHAIN6(X0, X1, X2, X3, X4, X5) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN5(X1, X2, X3, X4, X5) >
380 #define _GLIBCXX_TYPELIST_CHAIN7(X0, X1, X2, X3, X4, X5, X6) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN6(X1, X2, X3, X4, X5, X6) >
381 #define _GLIBCXX_TYPELIST_CHAIN8(X0, X1, X2, X3, X4, X5, X6, X7) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN7(X1, X2, X3, X4, X5, X6, X7) >
382 #define _GLIBCXX_TYPELIST_CHAIN9(X0, X1, X2, X3, X4, X5, X6, X7, X8) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN8(X1, X2, X3, X4, X5, X6, X7, X8) >
383 #define _GLIBCXX_TYPELIST_CHAIN10(X0, X1, X2, X3, X4, X5, X6, X7, X8, X9) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN9(X1, X2, X3, X4, X5, X6, X7, X8, X9) >
384 #define _GLIBCXX_TYPELIST_CHAIN11(X0, X1, X2, X3, X4, X5, X6, X7, X8, X9, X10) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN10(X1, X2, X3, X4, X5, X6, X7, X8, X9, X10) >
385 #define _GLIBCXX_TYPELIST_CHAIN12(X0, X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN11(X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11) >
386 #define _GLIBCXX_TYPELIST_CHAIN13(X0, X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN12(X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12) >
387 #define _GLIBCXX_TYPELIST_CHAIN14(X0, X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12, X13) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN13(X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12, X13) >
388 #define _GLIBCXX_TYPELIST_CHAIN15(X0, X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12, X13, X14) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN14(X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12, X13, X14) >
389 #define _GLIBCXX_TYPELIST_CHAIN16(X0, X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12, X13, X14, X15) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN15(X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12, X13, X14, X15) >
390 #define _GLIBCXX_TYPELIST_CHAIN17(X0, X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12, X13, X14, X15, X16) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN16(X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12, X13, X14, X15, X16) >
391 #define _GLIBCXX_TYPELIST_CHAIN18(X0, X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12, X13, X14, X15, X16, X17) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN17(X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12, X13, X14, X15, X16, X17) >
392 #define _GLIBCXX_TYPELIST_CHAIN19(X0, X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12, X13, X14, X15, X16, X17, X18) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN18(X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12, X13, X14, X15, X16, X17, X18) >
393 #define _GLIBCXX_TYPELIST_CHAIN20(X0, X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12, X13, X14, X15, X16, X17, X18, X19) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN19(X1, X2, X3, X4, X5, X6, X7, X8, X9, X10, X11, X12, X13, X14, X15, X16, X17, X18, X19) >
394 
395 namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
396 {
397 _GLIBCXX_BEGIN_NAMESPACE_VERSION
398 
399 namespace typelist
400 {
401  template<typename Fn, typename Typelist>
402  void
403  apply(Fn& fn, Typelist)
404  {
405  detail::apply_<Fn, typename Typelist::root> a;
406  a(fn);
407  }
408 
409  template<typename Fn, typename Typelist>
410  void
411  apply_generator(Fn& fn, Typelist)
412  {
413  detail::apply_generator1_<Fn, typename Typelist::root> a;
414  a(fn);
415  }
416 
417  template<typename Fn, typename TypelistT, typename TypelistV>
418  void
419  apply_generator(Fn& fn, TypelistT, TypelistV)
420  {
421  typedef typename TypelistT::root rootT;
422  typedef typename TypelistV::root rootV;
423  detail::apply_generator2_<Fn, rootT, rootV> a;
424  a(fn);
425  }
426 
427  template<typename Typelist0, typename Typelist1>
428  struct append
429  {
430  private:
431  typedef typename Typelist0::root root0_type;
432  typedef typename Typelist1::root root1_type;
433  typedef detail::append_<root0_type, root1_type> append_type;
434 
435  public:
436  typedef node<typename append_type::type> type;
437  };
438 
439  template<typename Typelist_Typelist>
440  struct append_typelist
441  {
442  private:
443  typedef typename Typelist_Typelist::root root_type;
444  typedef detail::append_typelist_<root_type> append_type;
445 
446  public:
447  typedef node<typename append_type::type> type;
448  };
449 
450  template<typename Typelist, typename T>
451  struct contains
452  {
453  private:
454  typedef typename Typelist::root root_type;
455 
456  public:
457  enum
458  {
459  value = detail::contains_<root_type, T>::value
460  };
461  };
462 
463  template<typename Typelist, template<typename T> class Pred>
464  struct filter
465  {
466  private:
467  typedef typename Typelist::root root_type;
468  typedef detail::chain_filter_<root_type, Pred> filter_type;
469 
470  public:
471  typedef node<typename filter_type::type> type;
472  };
473 
474  template<typename Typelist, int i>
475  struct at_index
476  {
477  private:
478  typedef typename Typelist::root root_type;
479  typedef detail::chain_at_index_<root_type, i> index_type;
480 
481  public:
482  typedef typename index_type::type type;
483  };
484 
485  template<typename Typelist, template<typename T> class Transform>
486  struct transform
487  {
488  private:
489  typedef typename Typelist::root root_type;
490  typedef detail::chain_transform_<root_type, Transform> transform_type;
491 
492  public:
493  typedef node<typename transform_type::type> type;
494  };
495 
496  template<typename Typelist_Typelist>
497  struct flatten
498  {
499  private:
500  typedef typename Typelist_Typelist::root root_type;
501  typedef typename detail::chain_flatten_<root_type>::type flatten_type;
502 
503  public:
504  typedef node<flatten_type> type;
505  };
506 
507  template<typename Typelist>
508  struct from_first
509  {
510  private:
511  typedef typename at_index<Typelist, 0>::type first_type;
512 
513  public:
514  typedef node<chain<first_type, null_type> > type;
515  };
516 
517  template<typename T1>
518  struct create1
519  {
520  typedef node<_GLIBCXX_TYPELIST_CHAIN1(T1)> type;
521  };
522 
523  template<typename T1, typename T2>
524  struct create2
525  {
526  typedef node<_GLIBCXX_TYPELIST_CHAIN2(T1,T2)> type;
527  };
528 
529  template<typename T1, typename T2, typename T3>
530  struct create3
531  {
532  typedef node<_GLIBCXX_TYPELIST_CHAIN3(T1,T2,T3)> type;
533  };
534 
535  template<typename T1, typename T2, typename T3, typename T4>
536  struct create4
537  {
538  typedef node<_GLIBCXX_TYPELIST_CHAIN4(T1,T2,T3,T4)> type;
539  };
540 
541  template<typename T1, typename T2, typename T3,
542  typename T4, typename T5>
543  struct create5
544  {
545  typedef node<_GLIBCXX_TYPELIST_CHAIN5(T1,T2,T3,T4,T5)> type;
546  };
547 
548  template<typename T1, typename T2, typename T3,
549  typename T4, typename T5, typename T6>
550  struct create6
551  {
552  typedef node<_GLIBCXX_TYPELIST_CHAIN6(T1,T2,T3,T4,T5,T6)> type;
553  };
554 } // namespace typelist
555 _GLIBCXX_END_NAMESPACE_VERSION
556 } // namespace
557 
558 
559 #endif
__gnu_cxx::typelist::apply_generator
void apply_generator(Gn &, Typelist)
Apply all typelist types to generator functor.
__gnu_cxx
GNU extensions for public use.