# typelist.h

Go to the documentation of this file.

    00001 // -*- C++ -*-
    00002
    00003 // Copyright (C) 2005, 2006 Free Software Foundation, Inc.
    00004 //
    00005 // This file is part of the GNU ISO C++ Library.  This library is free
    00006 // software; you can redistribute it and/or modify it under the
    00007 // terms of the GNU General Public License as published by the
    00008 // Free Software Foundation; either version 2, or (at your option)
    00009 // any later version.
    00010
    00011 // This library is distributed in the hope that it will be useful,
    00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
    00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    00014 // GNU General Public License for more details.
    00015
    00016 // You should have received a copy of the GNU General Public License along
    00017 // with this library; see the file COPYING.  If not, write to the Free
    00018 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
    00019 // USA.
    00020
    00021 // As a special exception, you may use this file as part of a free software
    00022 // library without restriction.  Specifically, if other files instantiate
    00023 // templates or use macros or inline functions from this file, or you compile
    00024 // this file and link it with other files to produce an executable, this
    00025 // file does not by itself cause the resulting executable to be covered by
    00026 // the GNU General Public License.  This exception does not however
    00027 // invalidate any other reasons why the executable file might be covered by
    00028 // the GNU General Public License.
    00029
    00030 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
    00031
    00032 // Permission to use, copy, modify, sell, and distribute this software
    00033 // is hereby granted without fee, provided that the above copyright
    00034 // notice appears in all copies, and that both that copyright notice and
    00035 // this permission notice appear in supporting documentation. None of
    00036 // the above authors, nor IBM Haifa Research Laboratories, make any
    00037 // representation about the suitability of this software for any
    00038 // purpose. It is provided "as is" without express or implied warranty.
    00039
    00040 /**
    00041  * @file typelist.h
    00042  * Contains typelist_chain definitions.
    00043  * Typelists are an idea by Andrei Alexandrescu.
    00044  */
    00045
    00046 #ifndef _TYPELIST_H
    00047 #define _TYPELIST_H 1
    00048
    00049 #include <ext/type_traits.h>
    00050
    00051 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
    00052
    00053 namespace typelist
    00054 {
    00055   struct null_type { };
    00056
    00057   template<typename Root>
    00058     struct node
    00059     {
    00060       typedef Root  root;
    00061     };
    00062
    00063   // Forward declarations of functors.
    00064   template<typename Hd, typename Typelist>
    00065     struct chain
    00066     {
    00067       typedef Hd    head;
    00068       typedef Typelist  tail;
    00069     };
    00070
    00071   template<typename Fn, class Typelist>
    00072     void
    00073     apply(Fn&, Typelist);
    00074
    00075   template<typename Typelist0, typename Typelist1>
    00076     struct append;
    00077
    00078   template<typename Typelist_Typelist>
    00079     struct append_typelist;
    00080
    00081   template<typename Typelist, typename T>
    00082     struct contains;
    00083
    00084   template<typename Typelist, template<typename T> class Pred>
    00085     struct filter;
    00086
    00087   template<typename Typelist, int i>
    00088     struct at_index;
    00089
    00090   template<typename Typelist, template<typename T> class Transform>
    00091     struct transform;
    00092
    00093   template<typename Typelist_Typelist>
    00094     struct flatten;
    00095
    00096   template<typename Typelist>
    00097     struct from_first;
    00098
    00099   template<typename T1>
    00100     struct create1;
    00101
    00102   template<typename T1, typename T2>
    00103     struct create2;
    00104
    00105   template<typename T1, typename T2, typename T3>
    00106     struct create3;
    00107
    00108   template<typename T1, typename T2, typename T3, typename T4>
    00109     struct create4;
    00110
    00111   template<typename T1, typename T2, typename T3, typename T4, typename T5>
    00112     struct create5;
    00113
    00114   template<typename T1, typename T2, typename T3,
    00115        typename T4, typename T5, typename T6>
    00116     struct create6;
    00117 } // namespace typelist
    00118
    00119 _GLIBCXX_END_NAMESPACE
    00120
    00121
    00122 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
    00123
    00124 namespace typelist
    00125 {
    00126 namespace detail
    00127 {
    00128   template<typename Fn, typename Typelist_Chain>
    00129     struct apply_;
    00130
    00131   template<typename Fn, typename Hd, typename Tl>
    00132     struct apply_<Fn, chain<Hd, Tl> >
    00133     {
    00134       void
    00135       operator() (Fn& f)
    00136       {
    00137     f.operator()(Hd());
    00138     apply_<Fn, Tl> next;
    00139     next(f);
    00140       }
    00141   };
    00142
    00143   template<typename Fn>
    00144     struct apply_<Fn, null_type>
    00145     {
    00146       void
    00147       operator()(Fn&) { }
    00148   };
    00149
    00150   template<typename Typelist_Chain0, typename Typelist_Chain1>
    00151     struct append_;
    00152
    00153   template<typename Hd, typename Tl, typename Typelist_Chain>
    00154     struct append_<chain<Hd, Tl>, Typelist_Chain>
    00155     {
    00156     private:
    00157       typedef append_<Tl, Typelist_Chain>           append_type;
    00158
    00159     public:
    00160       typedef chain<Hd, typename append_type::type>         type;
    00161     };
    00162
    00163   template<typename Typelist_Chain>
    00164     struct append_<null_type, Typelist_Chain>
    00165     {
    00166       typedef Typelist_Chain                        type;
    00167     };
    00168
    00169   template<typename Typelist_Chain>
    00170     struct append_<Typelist_Chain, null_type>
    00171     {
    00172       typedef Typelist_Chain                    type;
    00173     };
    00174
    00175   template<>
    00176     struct append_<null_type, null_type>
    00177     {
    00178       typedef null_type                     type;
    00179     };
    00180
    00181   template<typename Typelist_Typelist_Chain>
    00182     struct append_typelist_;
    00183
    00184   template<typename Hd>
    00185     struct append_typelist_<chain<Hd, null_type> >
    00186     {
    00187       typedef chain<Hd, null_type>              type;
    00188     };
    00189
    00190   template<typename Hd, typename Tl>
    00191     struct append_typelist_<chain< Hd, Tl> >
    00192     {
    00193     private:
    00194       typedef typename append_typelist_<Tl>::type       rest_type;
    00195
    00196     public:
    00197       typedef typename append<Hd, node<rest_type> >::type::root type;
    00198     };
    00199
    00200   template<typename Typelist_Chain, typename T>
    00201     struct contains_;
    00202
    00203   template<typename T>
    00204     struct contains_<null_type, T>
    00205     {
    00206       enum
    00207     {
    00208       value = false
    00209     };
    00210     };
    00211
    00212   template<typename Hd, typename Tl, typename T>
    00213     struct contains_<chain<Hd, Tl>, T>
    00214     {
    00215       enum
    00216     {
    00217       value = contains_<Tl, T>::value
    00218     };
    00219     };
    00220
    00221   template<typename Tl, typename T>
    00222     struct contains_<chain<T, Tl>, T>
    00223     {
    00224       enum
    00225     {
    00226       value = true
    00227     };
    00228     };
    00229
    00230   template<typename Typelist_Chain, template<typename T> class Pred>
    00231     struct chain_filter_;
    00232
    00233   template<template<typename T> class Pred>
    00234     struct chain_filter_<null_type, Pred>
    00235     {
    00236       typedef null_type                     type;
    00237   };
    00238
    00239   template<typename Hd, typename Tl, template<typename T> class Pred>
    00240     struct chain_filter_<chain<Hd, Tl>, Pred>
    00241     {
    00242     private:
    00243       enum
    00244     {
    00245       include_hd = Pred<Hd>::value
    00246     };
    00247
    00248       typedef typename chain_filter_<Tl, Pred>::type        rest_type;
    00249       typedef chain<Hd, rest_type>              chain_type;
    00250
    00251     public:
    00252       typedef typename __conditional_type<include_hd, chain_type, rest_type>::__type type;
    00253   };
    00254
    00255   template<typename Typelist_Chain, int i>
    00256     struct chain_at_index_;
    00257
    00258   template<typename Hd, typename Tl>
    00259     struct chain_at_index_<chain<Hd, Tl>, 0>
    00260     {
    00261       typedef Hd                        type;
    00262     };
    00263
    00264   template<typename Hd, typename Tl, int i>
    00265     struct chain_at_index_<chain<Hd, Tl>, i>
    00266     {
    00267       typedef typename chain_at_index_<Tl, i - 1>::type     type;
    00268     };
    00269
    00270   template<class Typelist_Chain, template<typename T> class Transform>
    00271     struct chain_transform_;
    00272
    00273   template<template<typename T> class Transform>
    00274     struct chain_transform_<null_type, Transform>
    00275     {
    00276       typedef null_type                     type;
    00277     };
    00278
    00279   template<class Hd, class Tl, template<typename T> class Transform>
    00280     struct chain_transform_<chain<Hd, Tl>, Transform>
    00281     {
    00282     private:
    00283       typedef typename chain_transform_<Tl, Transform>::type    rest_type;
    00284       typedef typename Transform<Hd>::type          transform_type;
    00285
    00286     public:
    00287       typedef chain<transform_type, rest_type>          type;
    00288     };
    00289
    00290   template<typename Typelist_Typelist_Chain>
    00291     struct chain_flatten_;
    00292
    00293   template<typename Hd_Tl>
    00294   struct chain_flatten_<chain<Hd_Tl, null_type> >
    00295   {
    00296     typedef typename Hd_Tl::root                type;
    00297   };
    00298
    00299   template<typename Hd_Typelist, class Tl_Typelist>
    00300   struct chain_flatten_<chain<Hd_Typelist, Tl_Typelist> >
    00301   {
    00302   private:
    00303     typedef typename chain_flatten_<Tl_Typelist>::type      rest_type;
    00304     typedef append<Hd_Typelist, node<rest_type> >       append_type;
    00305   public:
    00306     typedef typename append_type::type::root            type;
    00307   };
    00308 } // namespace detail
    00309 } // namespace typelist
    00310
    00311 _GLIBCXX_END_NAMESPACE
    00312
    00313 #define _GLIBCXX_TYPELIST_CHAIN1(X0) __gnu_cxx::typelist::chain<X0, __gnu_cxx::typelist::null_type>
    00314 #define _GLIBCXX_TYPELIST_CHAIN2(X0, X1) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN1(X1) >
    00315 #define _GLIBCXX_TYPELIST_CHAIN3(X0, X1, X2) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN2(X1, X2) >
    00316 #define _GLIBCXX_TYPELIST_CHAIN4(X0, X1, X2, X3) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN3(X1, X2, X3) >
    00317 #define _GLIBCXX_TYPELIST_CHAIN5(X0, X1, X2, X3, X4) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN4(X1, X2, X3, X4) >
    00318 #define _GLIBCXX_TYPELIST_CHAIN6(X0, X1, X2, X3, X4, X5) __gnu_cxx::typelist::chain<X0, _GLIBCXX_TYPELIST_CHAIN5(X1, X2, X3, X4, X5) >
    00319 #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) >
    00320 #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) >
    00321 #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) >
    00322 #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) >
    00323 #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) >
    00324 #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) >
    00325 #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) >
    00326 #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) >
    00327 #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) >
    00328
    00329 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
    00330
    00331 namespace typelist
    00332 {
    00333   template<typename Fn, class Typelist>
    00334     void
    00335     apply(Fn& fn, Typelist)
    00336     {
    00337       detail::apply_<Fn, typename Typelist::root> a;
    00338       a(fn);
    00339     }
    00340
    00341   template<typename Typelist0, typename Typelist1>
    00342     struct append
    00343     {
    00344     private:
    00345       typedef typename Typelist0::root              root0_type;
    00346       typedef typename Typelist1::root              root1_type;
    00347       typedef detail::append_<root0_type, root1_type>       append_type;
    00348
    00349     public:
    00350       typedef node<typename append_type::type>          type;
    00351     };
    00352
    00353   template<typename Typelist_Typelist>
    00354     struct append_typelist
    00355     {
    00356     private:
    00357       typedef typename Typelist_Typelist::root              root_type;
    00358       typedef detail::append_typelist_<root_type>       append_type;
    00359
    00360     public:
    00361       typedef node<typename append_type::type>          type;
    00362     };
    00363
    00364   template<typename Typelist, typename T>
    00365     struct contains
    00366     {
    00367     private:
    00368       typedef typename Typelist::root               root_type;
    00369
    00370     public:
    00371       enum
    00372     {
    00373       value = detail::contains_<root_type, T>::value
    00374     };
    00375     };
    00376
    00377   template<typename Typelist, template<typename T> class Pred>
    00378     struct filter
    00379     {
    00380     private:
    00381       typedef typename Typelist::root               root_type;
    00382       typedef detail::chain_filter_<root_type, Pred>        filter_type;
    00383
    00384     public:
    00385       typedef node<typename filter_type::type>              type;
    00386     };
    00387
    00388   template<typename Typelist, int i>
    00389     struct at_index
    00390     {
    00391     private:
    00392       typedef typename Typelist::root               root_type;
    00393       typedef detail::chain_at_index_<root_type, i>         index_type;
    00394
    00395     public:
    00396       typedef typename index_type::type             type;
    00397     };
    00398
    00399   template<typename Typelist, template<typename T> class Transform>
    00400     struct transform
    00401     {
    00402     private:
    00403       typedef typename Typelist::root               root_type;
    00404       typedef detail::chain_transform_<root_type, Transform>    transform_type;
    00405
    00406     public:
    00407       typedef node<typename transform_type::type>       type;
    00408     };
    00409
    00410   template<typename Typelist_Typelist>
    00411     struct flatten
    00412     {
    00413     private:
    00414       typedef typename Typelist_Typelist::root              root_type;
    00415       typedef typename detail::chain_flatten_<root_type>::type  flatten_type;
    00416
    00417     public:
    00418       typedef node<flatten_type>                type;
    00419     };
    00420
    00421   template<typename Typelist>
    00422     struct from_first
    00423     {
    00424     private:
    00425       typedef typename at_index<Typelist, 0>::type      first_type;
    00426
    00427     public:
    00428       typedef node<chain<first_type, null_type> >       type;
    00429     };
    00430
    00431   template<typename T1>
    00432     struct create1
    00433     {
    00434       typedef node<_GLIBCXX_TYPELIST_CHAIN1(T1)>        type;
    00435     };
    00436
    00437   template<typename T1, typename T2>
    00438     struct create2
    00439     {
    00440       typedef node<_GLIBCXX_TYPELIST_CHAIN2(T1,T2)>         type;
    00441     };
    00442
    00443   template<typename T1, typename T2, typename T3>
    00444     struct create3
    00445     {
    00446       typedef node<_GLIBCXX_TYPELIST_CHAIN3(T1,T2,T3)>      type;
    00447     };
    00448
    00449   template<typename T1, typename T2, typename T3, typename T4>
    00450     struct create4
    00451     {
    00452       typedef node<_GLIBCXX_TYPELIST_CHAIN4(T1,T2,T3,T4)>   type;
    00453     };
    00454
    00455   template<typename T1, typename T2, typename T3,
    00456        typename T4, typename T5>
    00457     struct create5
    00458     {
    00459       typedef node<_GLIBCXX_TYPELIST_CHAIN5(T1,T2,T3,T4,T5)>    type;
    00460     };
    00461
    00462   template<typename T1, typename T2, typename T3,
    00463        typename T4, typename T5, typename T6>
    00464     struct create6
    00465     {
    00466       typedef node<_GLIBCXX_TYPELIST_CHAIN6(T1,T2,T3,T4,T5,T6)> type;
    00467     };
    00468 } // namespace typelist
    00469 _GLIBCXX_END_NAMESPACE
    00470
    00471
    00472 #endif
    00473