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      1 // Functor implementations -*- C++ -*-
      2 
      3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2009
      4 // Free Software Foundation, Inc.
      5 //
      6 // This file is part of the GNU ISO C++ Library.  This library is free
      7 // software; you can redistribute it and/or modify it under the
      8 // terms of the GNU General Public License as published by the
      9 // Free Software Foundation; either version 3, or (at your option)
     10 // any later version.
     11 
     12 // This library is distributed in the hope that it will be useful,
     13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
     14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     15 // GNU General Public License for more details.
     16 
     17 // Under Section 7 of GPL version 3, you are granted additional
     18 // permissions described in the GCC Runtime Library Exception, version
     19 // 3.1, as published by the Free Software Foundation.
     20 
     21 // You should have received a copy of the GNU General Public License and
     22 // a copy of the GCC Runtime Library Exception along with this program;
     23 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
     24 // <http://www.gnu.org/licenses/>.
     25 
     26 /*
     27  *
     28  * Copyright (c) 1994
     29  * Hewlett-Packard Company
     30  *
     31  * Permission to use, copy, modify, distribute and sell this software
     32  * and its documentation for any purpose is hereby granted without fee,
     33  * provided that the above copyright notice appear in all copies and
     34  * that both that copyright notice and this permission notice appear
     35  * in supporting documentation.  Hewlett-Packard Company makes no
     36  * representations about the suitability of this software for any
     37  * purpose.  It is provided "as is" without express or implied warranty.
     38  *
     39  *
     40  * Copyright (c) 1996-1998
     41  * Silicon Graphics Computer Systems, Inc.
     42  *
     43  * Permission to use, copy, modify, distribute and sell this software
     44  * and its documentation for any purpose is hereby granted without fee,
     45  * provided that the above copyright notice appear in all copies and
     46  * that both that copyright notice and this permission notice appear
     47  * in supporting documentation.  Silicon Graphics makes no
     48  * representations about the suitability of this software for any
     49  * purpose.  It is provided "as is" without express or implied warranty.
     50  */
     51 
     52 /** @file stl_function.h
     53  *  This is an internal header file, included by other library headers.
     54  *  You should not attempt to use it directly.
     55  */
     56 
     57 #ifndef _STL_FUNCTION_H
     58 #define _STL_FUNCTION_H 1
     59 
     60 _GLIBCXX_BEGIN_NAMESPACE(std)
     61 
     62   // 20.3.1 base classes
     63   /** @defgroup functors Function Objects
     64    * @ingroup utilities
     65    *
     66    *  Function objects, or @e functors, are objects with an @c operator()
     67    *  defined and accessible.  They can be passed as arguments to algorithm
     68    *  templates and used in place of a function pointer.  Not only is the
     69    *  resulting expressiveness of the library increased, but the generated
     70    *  code can be more efficient than what you might write by hand.  When we
     71    *  refer to "functors," then, generally we include function pointers in
     72    *  the description as well.
     73    *
     74    *  Often, functors are only created as temporaries passed to algorithm
     75    *  calls, rather than being created as named variables.
     76    *
     77    *  Two examples taken from the standard itself follow.  To perform a
     78    *  by-element addition of two vectors @c a and @c b containing @c double,
     79    *  and put the result in @c a, use
     80    *  \code
     81    *  transform (a.begin(), a.end(), b.begin(), a.begin(), plus<double>());
     82    *  \endcode
     83    *  To negate every element in @c a, use
     84    *  \code
     85    *  transform(a.begin(), a.end(), a.begin(), negate<double>());
     86    *  \endcode
     87    *  The addition and negation functions will be inlined directly.
     88    *
     89    *  The standard functors are derived from structs named @c unary_function
     90    *  and @c binary_function.  These two classes contain nothing but typedefs,
     91    *  to aid in generic (template) programming.  If you write your own
     92    *  functors, you might consider doing the same.
     93    *
     94    *  @{
     95    */
     96   /**
     97    *  This is one of the @link functors functor base classes@endlink.
     98    */
     99   template<typename _Arg, typename _Result>
    100     struct unary_function
    101     {
    102       typedef _Arg argument_type;   ///< @c argument_type is the type of the
    103                                     ///     argument (no surprises here)
    104 
    105       typedef _Result result_type;  ///< @c result_type is the return type
    106     };
    107 
    108   /**
    109    *  This is one of the @link functors functor base classes@endlink.
    110    */
    111   template<typename _Arg1, typename _Arg2, typename _Result>
    112     struct binary_function
    113     {
    114       typedef _Arg1 first_argument_type;   ///< the type of the first argument
    115                                            ///  (no surprises here)
    116 
    117       typedef _Arg2 second_argument_type;  ///< the type of the second argument
    118       typedef _Result result_type;         ///< type of the return type
    119     };
    120   /** @}  */
    121 
    122   // 20.3.2 arithmetic
    123   /** @defgroup arithmetic_functors Arithmetic Classes
    124    * @ingroup functors
    125    *
    126    *  Because basic math often needs to be done during an algorithm,
    127    *  the library provides functors for those operations.  See the
    128    *  documentation for @link functors the base classes@endlink
    129    *  for examples of their use.
    130    *
    131    *  @{
    132    */
    133   /// One of the @link arithmetic_functors math functors@endlink.
    134   template<typename _Tp>
    135     struct plus : public binary_function<_Tp, _Tp, _Tp>
    136     {
    137       _Tp
    138       operator()(const _Tp& __x, const _Tp& __y) const
    139       { return __x + __y; }
    140     };
    141 
    142   /// One of the @link arithmetic_functors math functors@endlink.
    143   template<typename _Tp>
    144     struct minus : public binary_function<_Tp, _Tp, _Tp>
    145     {
    146       _Tp
    147       operator()(const _Tp& __x, const _Tp& __y) const
    148       { return __x - __y; }
    149     };
    150 
    151   /// One of the @link arithmetic_functors math functors@endlink.
    152   template<typename _Tp>
    153     struct multiplies : public binary_function<_Tp, _Tp, _Tp>
    154     {
    155       _Tp
    156       operator()(const _Tp& __x, const _Tp& __y) const
    157       { return __x * __y; }
    158     };
    159 
    160   /// One of the @link arithmetic_functors math functors@endlink.
    161   template<typename _Tp>
    162     struct divides : public binary_function<_Tp, _Tp, _Tp>
    163     {
    164       _Tp
    165       operator()(const _Tp& __x, const _Tp& __y) const
    166       { return __x / __y; }
    167     };
    168 
    169   /// One of the @link arithmetic_functors math functors@endlink.
    170   template<typename _Tp>
    171     struct modulus : public binary_function<_Tp, _Tp, _Tp>
    172     {
    173       _Tp
    174       operator()(const _Tp& __x, const _Tp& __y) const
    175       { return __x % __y; }
    176     };
    177 
    178   /// One of the @link arithmetic_functors math functors@endlink.
    179   template<typename _Tp>
    180     struct negate : public unary_function<_Tp, _Tp>
    181     {
    182       _Tp
    183       operator()(const _Tp& __x) const
    184       { return -__x; }
    185     };
    186   /** @}  */
    187 
    188   // 20.3.3 comparisons
    189   /** @defgroup comparison_functors Comparison Classes
    190    * @ingroup functors
    191    *
    192    *  The library provides six wrapper functors for all the basic comparisons
    193    *  in C++, like @c <.
    194    *
    195    *  @{
    196    */
    197   /// One of the @link comparison_functors comparison functors@endlink.
    198   template<typename _Tp>
    199     struct equal_to : public binary_function<_Tp, _Tp, bool>
    200     {
    201       bool
    202       operator()(const _Tp& __x, const _Tp& __y) const
    203       { return __x == __y; }
    204     };
    205 
    206   /// One of the @link comparison_functors comparison functors@endlink.
    207   template<typename _Tp>
    208     struct not_equal_to : public binary_function<_Tp, _Tp, bool>
    209     {
    210       bool
    211       operator()(const _Tp& __x, const _Tp& __y) const
    212       { return __x != __y; }
    213     };
    214 
    215   /// One of the @link comparison_functors comparison functors@endlink.
    216   template<typename _Tp>
    217     struct greater : public binary_function<_Tp, _Tp, bool>
    218     {
    219       bool
    220       operator()(const _Tp& __x, const _Tp& __y) const
    221       { return __x > __y; }
    222     };
    223 
    224   /// One of the @link comparison_functors comparison functors@endlink.
    225   template<typename _Tp>
    226     struct less : public binary_function<_Tp, _Tp, bool>
    227     {
    228       bool
    229       operator()(const _Tp& __x, const _Tp& __y) const
    230       { return __x < __y; }
    231     };
    232 
    233   /// One of the @link comparison_functors comparison functors@endlink.
    234   template<typename _Tp>
    235     struct greater_equal : public binary_function<_Tp, _Tp, bool>
    236     {
    237       bool
    238       operator()(const _Tp& __x, const _Tp& __y) const
    239       { return __x >= __y; }
    240     };
    241 
    242   /// One of the @link comparison_functors comparison functors@endlink.
    243   template<typename _Tp>
    244     struct less_equal : public binary_function<_Tp, _Tp, bool>
    245     {
    246       bool
    247       operator()(const _Tp& __x, const _Tp& __y) const
    248       { return __x <= __y; }
    249     };
    250   /** @}  */
    251 
    252   // 20.3.4 logical operations
    253   /** @defgroup logical_functors Boolean Operations Classes
    254    * @ingroup functors
    255    *
    256    *  Here are wrapper functors for Boolean operations: @c &&, @c ||,
    257    *  and @c !.
    258    *
    259    *  @{
    260    */
    261   /// One of the @link logical_functors Boolean operations functors@endlink.
    262   template<typename _Tp>
    263     struct logical_and : public binary_function<_Tp, _Tp, bool>
    264     {
    265       bool
    266       operator()(const _Tp& __x, const _Tp& __y) const
    267       { return __x && __y; }
    268     };
    269 
    270   /// One of the @link logical_functors Boolean operations functors@endlink.
    271   template<typename _Tp>
    272     struct logical_or : public binary_function<_Tp, _Tp, bool>
    273     {
    274       bool
    275       operator()(const _Tp& __x, const _Tp& __y) const
    276       { return __x || __y; }
    277     };
    278 
    279   /// One of the @link logical_functors Boolean operations functors@endlink.
    280   template<typename _Tp>
    281     struct logical_not : public unary_function<_Tp, bool>
    282     {
    283       bool
    284       operator()(const _Tp& __x) const
    285       { return !__x; }
    286     };
    287   /** @}  */
    288 
    289   // _GLIBCXX_RESOLVE_LIB_DEFECTS
    290   // DR 660. Missing Bitwise Operations.
    291   template<typename _Tp>
    292     struct bit_and : public binary_function<_Tp, _Tp, _Tp>
    293     {
    294       _Tp
    295       operator()(const _Tp& __x, const _Tp& __y) const
    296       { return __x & __y; }
    297     };
    298 
    299   template<typename _Tp>
    300     struct bit_or : public binary_function<_Tp, _Tp, _Tp>
    301     {
    302       _Tp
    303       operator()(const _Tp& __x, const _Tp& __y) const
    304       { return __x | __y; }
    305     };
    306 
    307   template<typename _Tp>
    308     struct bit_xor : public binary_function<_Tp, _Tp, _Tp>
    309     {
    310       _Tp
    311       operator()(const _Tp& __x, const _Tp& __y) const
    312       { return __x ^ __y; }
    313     };
    314 
    315   // 20.3.5 negators
    316   /** @defgroup negators Negators
    317    * @ingroup functors
    318    *
    319    *  The functions @c not1 and @c not2 each take a predicate functor
    320    *  and return an instance of @c unary_negate or
    321    *  @c binary_negate, respectively.  These classes are functors whose
    322    *  @c operator() performs the stored predicate function and then returns
    323    *  the negation of the result.
    324    *
    325    *  For example, given a vector of integers and a trivial predicate,
    326    *  \code
    327    *  struct IntGreaterThanThree
    328    *    : public std::unary_function<int, bool>
    329    *  {
    330    *      bool operator() (int x) { return x > 3; }
    331    *  };
    332    *
    333    *  std::find_if (v.begin(), v.end(), not1(IntGreaterThanThree()));
    334    *  \endcode
    335    *  The call to @c find_if will locate the first index (i) of @c v for which
    336    *  "!(v[i] > 3)" is true.
    337    *
    338    *  The not1/unary_negate combination works on predicates taking a single
    339    *  argument.  The not2/binary_negate combination works on predicates which
    340    *  take two arguments.
    341    *
    342    *  @{
    343    */
    344   /// One of the @link negators negation functors@endlink.
    345   template<typename _Predicate>
    346     class unary_negate
    347     : public unary_function<typename _Predicate::argument_type, bool>
    348     {
    349     protected:
    350       _Predicate _M_pred;
    351 
    352     public:
    353       explicit
    354       unary_negate(const _Predicate& __x) : _M_pred(__x) { }
    355 
    356       bool
    357       operator()(const typename _Predicate::argument_type& __x) const
    358       { return !_M_pred(__x); }
    359     };
    360 
    361   /// One of the @link negators negation functors@endlink.
    362   template<typename _Predicate>
    363     inline unary_negate<_Predicate>
    364     not1(const _Predicate& __pred)
    365     { return unary_negate<_Predicate>(__pred); }
    366 
    367   /// One of the @link negators negation functors@endlink.
    368   template<typename _Predicate>
    369     class binary_negate
    370     : public binary_function<typename _Predicate::first_argument_type,
    371 			     typename _Predicate::second_argument_type, bool>
    372     {
    373     protected:
    374       _Predicate _M_pred;
    375 
    376     public:
    377       explicit
    378       binary_negate(const _Predicate& __x) : _M_pred(__x) { }
    379 
    380       bool
    381       operator()(const typename _Predicate::first_argument_type& __x,
    382 		 const typename _Predicate::second_argument_type& __y) const
    383       { return !_M_pred(__x, __y); }
    384     };
    385 
    386   /// One of the @link negators negation functors@endlink.
    387   template<typename _Predicate>
    388     inline binary_negate<_Predicate>
    389     not2(const _Predicate& __pred)
    390     { return binary_negate<_Predicate>(__pred); }
    391   /** @}  */
    392 
    393   // 20.3.7 adaptors pointers functions
    394   /** @defgroup pointer_adaptors Adaptors for pointers to functions
    395    * @ingroup functors
    396    *
    397    *  The advantage of function objects over pointers to functions is that
    398    *  the objects in the standard library declare nested typedefs describing
    399    *  their argument and result types with uniform names (e.g., @c result_type
    400    *  from the base classes @c unary_function and @c binary_function).
    401    *  Sometimes those typedefs are required, not just optional.
    402    *
    403    *  Adaptors are provided to turn pointers to unary (single-argument) and
    404    *  binary (double-argument) functions into function objects.  The
    405    *  long-winded functor @c pointer_to_unary_function is constructed with a
    406    *  function pointer @c f, and its @c operator() called with argument @c x
    407    *  returns @c f(x).  The functor @c pointer_to_binary_function does the same
    408    *  thing, but with a double-argument @c f and @c operator().
    409    *
    410    *  The function @c ptr_fun takes a pointer-to-function @c f and constructs
    411    *  an instance of the appropriate functor.
    412    *
    413    *  @{
    414    */
    415   /// One of the @link pointer_adaptors adaptors for function pointers@endlink.
    416   template<typename _Arg, typename _Result>
    417     class pointer_to_unary_function : public unary_function<_Arg, _Result>
    418     {
    419     protected:
    420       _Result (*_M_ptr)(_Arg);
    421 
    422     public:
    423       pointer_to_unary_function() { }
    424 
    425       explicit
    426       pointer_to_unary_function(_Result (*__x)(_Arg))
    427       : _M_ptr(__x) { }
    428 
    429       _Result
    430       operator()(_Arg __x) const
    431       { return _M_ptr(__x); }
    432     };
    433 
    434   /// One of the @link pointer_adaptors adaptors for function pointers@endlink.
    435   template<typename _Arg, typename _Result>
    436     inline pointer_to_unary_function<_Arg, _Result>
    437     ptr_fun(_Result (*__x)(_Arg))
    438     { return pointer_to_unary_function<_Arg, _Result>(__x); }
    439 
    440   /// One of the @link pointer_adaptors adaptors for function pointers@endlink.
    441   template<typename _Arg1, typename _Arg2, typename _Result>
    442     class pointer_to_binary_function
    443     : public binary_function<_Arg1, _Arg2, _Result>
    444     {
    445     protected:
    446       _Result (*_M_ptr)(_Arg1, _Arg2);
    447 
    448     public:
    449       pointer_to_binary_function() { }
    450 
    451       explicit
    452       pointer_to_binary_function(_Result (*__x)(_Arg1, _Arg2))
    453       : _M_ptr(__x) { }
    454 
    455       _Result
    456       operator()(_Arg1 __x, _Arg2 __y) const
    457       { return _M_ptr(__x, __y); }
    458     };
    459 
    460   /// One of the @link pointer_adaptors adaptors for function pointers@endlink.
    461   template<typename _Arg1, typename _Arg2, typename _Result>
    462     inline pointer_to_binary_function<_Arg1, _Arg2, _Result>
    463     ptr_fun(_Result (*__x)(_Arg1, _Arg2))
    464     { return pointer_to_binary_function<_Arg1, _Arg2, _Result>(__x); }
    465   /** @}  */
    466 
    467   template<typename _Tp>
    468     struct _Identity : public unary_function<_Tp,_Tp>
    469     {
    470       _Tp&
    471       operator()(_Tp& __x) const
    472       { return __x; }
    473 
    474       const _Tp&
    475       operator()(const _Tp& __x) const
    476       { return __x; }
    477     };
    478 
    479   template<typename _Pair>
    480     struct _Select1st : public unary_function<_Pair,
    481 					      typename _Pair::first_type>
    482     {
    483       typename _Pair::first_type&
    484       operator()(_Pair& __x) const
    485       { return __x.first; }
    486 
    487       const typename _Pair::first_type&
    488       operator()(const _Pair& __x) const
    489       { return __x.first; }
    490     };
    491 
    492   template<typename _Pair>
    493     struct _Select2nd : public unary_function<_Pair,
    494 					      typename _Pair::second_type>
    495     {
    496       typename _Pair::second_type&
    497       operator()(_Pair& __x) const
    498       { return __x.second; }
    499 
    500       const typename _Pair::second_type&
    501       operator()(const _Pair& __x) const
    502       { return __x.second; }
    503     };
    504 
    505   // 20.3.8 adaptors pointers members
    506   /** @defgroup memory_adaptors Adaptors for pointers to members
    507    * @ingroup functors
    508    *
    509    *  There are a total of 8 = 2^3 function objects in this family.
    510    *   (1) Member functions taking no arguments vs member functions taking
    511    *        one argument.
    512    *   (2) Call through pointer vs call through reference.
    513    *   (3) Const vs non-const member function.
    514    *
    515    *  All of this complexity is in the function objects themselves.  You can
    516    *   ignore it by using the helper function mem_fun and mem_fun_ref,
    517    *   which create whichever type of adaptor is appropriate.
    518    *
    519    *  @{
    520    */
    521   /// One of the @link memory_adaptors adaptors for member
    522   /// pointers@endlink.
    523   template<typename _Ret, typename _Tp>
    524     class mem_fun_t : public unary_function<_Tp*, _Ret>
    525     {
    526     public:
    527       explicit
    528       mem_fun_t(_Ret (_Tp::*__pf)())
    529       : _M_f(__pf) { }
    530 
    531       _Ret
    532       operator()(_Tp* __p) const
    533       { return (__p->*_M_f)(); }
    534 
    535     private:
    536       _Ret (_Tp::*_M_f)();
    537     };
    538 
    539   /// One of the @link memory_adaptors adaptors for member
    540   /// pointers@endlink.
    541   template<typename _Ret, typename _Tp>
    542     class const_mem_fun_t : public unary_function<const _Tp*, _Ret>
    543     {
    544     public:
    545       explicit
    546       const_mem_fun_t(_Ret (_Tp::*__pf)() const)
    547       : _M_f(__pf) { }
    548 
    549       _Ret
    550       operator()(const _Tp* __p) const
    551       { return (__p->*_M_f)(); }
    552 
    553     private:
    554       _Ret (_Tp::*_M_f)() const;
    555     };
    556 
    557   /// One of the @link memory_adaptors adaptors for member
    558   /// pointers@endlink.
    559   template<typename _Ret, typename _Tp>
    560     class mem_fun_ref_t : public unary_function<_Tp, _Ret>
    561     {
    562     public:
    563       explicit
    564       mem_fun_ref_t(_Ret (_Tp::*__pf)())
    565       : _M_f(__pf) { }
    566 
    567       _Ret
    568       operator()(_Tp& __r) const
    569       { return (__r.*_M_f)(); }
    570 
    571     private:
    572       _Ret (_Tp::*_M_f)();
    573   };
    574 
    575   /// One of the @link memory_adaptors adaptors for member
    576   /// pointers@endlink.
    577   template<typename _Ret, typename _Tp>
    578     class const_mem_fun_ref_t : public unary_function<_Tp, _Ret>
    579     {
    580     public:
    581       explicit
    582       const_mem_fun_ref_t(_Ret (_Tp::*__pf)() const)
    583       : _M_f(__pf) { }
    584 
    585       _Ret
    586       operator()(const _Tp& __r) const
    587       { return (__r.*_M_f)(); }
    588 
    589     private:
    590       _Ret (_Tp::*_M_f)() const;
    591     };
    592 
    593   /// One of the @link memory_adaptors adaptors for member
    594   /// pointers@endlink.
    595   template<typename _Ret, typename _Tp, typename _Arg>
    596     class mem_fun1_t : public binary_function<_Tp*, _Arg, _Ret>
    597     {
    598     public:
    599       explicit
    600       mem_fun1_t(_Ret (_Tp::*__pf)(_Arg))
    601       : _M_f(__pf) { }
    602 
    603       _Ret
    604       operator()(_Tp* __p, _Arg __x) const
    605       { return (__p->*_M_f)(__x); }
    606 
    607     private:
    608       _Ret (_Tp::*_M_f)(_Arg);
    609     };
    610 
    611   /// One of the @link memory_adaptors adaptors for member
    612   /// pointers@endlink.
    613   template<typename _Ret, typename _Tp, typename _Arg>
    614     class const_mem_fun1_t : public binary_function<const _Tp*, _Arg, _Ret>
    615     {
    616     public:
    617       explicit
    618       const_mem_fun1_t(_Ret (_Tp::*__pf)(_Arg) const)
    619       : _M_f(__pf) { }
    620 
    621       _Ret
    622       operator()(const _Tp* __p, _Arg __x) const
    623       { return (__p->*_M_f)(__x); }
    624 
    625     private:
    626       _Ret (_Tp::*_M_f)(_Arg) const;
    627     };
    628 
    629   /// One of the @link memory_adaptors adaptors for member
    630   /// pointers@endlink.
    631   template<typename _Ret, typename _Tp, typename _Arg>
    632     class mem_fun1_ref_t : public binary_function<_Tp, _Arg, _Ret>
    633     {
    634     public:
    635       explicit
    636       mem_fun1_ref_t(_Ret (_Tp::*__pf)(_Arg))
    637       : _M_f(__pf) { }
    638 
    639       _Ret
    640       operator()(_Tp& __r, _Arg __x) const
    641       { return (__r.*_M_f)(__x); }
    642 
    643     private:
    644       _Ret (_Tp::*_M_f)(_Arg);
    645     };
    646 
    647   /// One of the @link memory_adaptors adaptors for member
    648   /// pointers@endlink.
    649   template<typename _Ret, typename _Tp, typename _Arg>
    650     class const_mem_fun1_ref_t : public binary_function<_Tp, _Arg, _Ret>
    651     {
    652     public:
    653       explicit
    654       const_mem_fun1_ref_t(_Ret (_Tp::*__pf)(_Arg) const)
    655       : _M_f(__pf) { }
    656 
    657       _Ret
    658       operator()(const _Tp& __r, _Arg __x) const
    659       { return (__r.*_M_f)(__x); }
    660 
    661     private:
    662       _Ret (_Tp::*_M_f)(_Arg) const;
    663     };
    664 
    665   // Mem_fun adaptor helper functions.  There are only two:
    666   // mem_fun and mem_fun_ref.
    667   template<typename _Ret, typename _Tp>
    668     inline mem_fun_t<_Ret, _Tp>
    669     mem_fun(_Ret (_Tp::*__f)())
    670     { return mem_fun_t<_Ret, _Tp>(__f); }
    671 
    672   template<typename _Ret, typename _Tp>
    673     inline const_mem_fun_t<_Ret, _Tp>
    674     mem_fun(_Ret (_Tp::*__f)() const)
    675     { return const_mem_fun_t<_Ret, _Tp>(__f); }
    676 
    677   template<typename _Ret, typename _Tp>
    678     inline mem_fun_ref_t<_Ret, _Tp>
    679     mem_fun_ref(_Ret (_Tp::*__f)())
    680     { return mem_fun_ref_t<_Ret, _Tp>(__f); }
    681 
    682   template<typename _Ret, typename _Tp>
    683     inline const_mem_fun_ref_t<_Ret, _Tp>
    684     mem_fun_ref(_Ret (_Tp::*__f)() const)
    685     { return const_mem_fun_ref_t<_Ret, _Tp>(__f); }
    686 
    687   template<typename _Ret, typename _Tp, typename _Arg>
    688     inline mem_fun1_t<_Ret, _Tp, _Arg>
    689     mem_fun(_Ret (_Tp::*__f)(_Arg))
    690     { return mem_fun1_t<_Ret, _Tp, _Arg>(__f); }
    691 
    692   template<typename _Ret, typename _Tp, typename _Arg>
    693     inline const_mem_fun1_t<_Ret, _Tp, _Arg>
    694     mem_fun(_Ret (_Tp::*__f)(_Arg) const)
    695     { return const_mem_fun1_t<_Ret, _Tp, _Arg>(__f); }
    696 
    697   template<typename _Ret, typename _Tp, typename _Arg>
    698     inline mem_fun1_ref_t<_Ret, _Tp, _Arg>
    699     mem_fun_ref(_Ret (_Tp::*__f)(_Arg))
    700     { return mem_fun1_ref_t<_Ret, _Tp, _Arg>(__f); }
    701 
    702   template<typename _Ret, typename _Tp, typename _Arg>
    703     inline const_mem_fun1_ref_t<_Ret, _Tp, _Arg>
    704     mem_fun_ref(_Ret (_Tp::*__f)(_Arg) const)
    705     { return const_mem_fun1_ref_t<_Ret, _Tp, _Arg>(__f); }
    706 
    707   /** @}  */
    708 
    709 _GLIBCXX_END_NAMESPACE
    710 
    711 #if !defined(__GXX_EXPERIMENTAL_CXX0X__) || _GLIBCXX_DEPRECATED
    712 # include <backward/binders.h>
    713 #endif
    714 
    715 #endif /* _STL_FUNCTION_H */
    716