📄 stl_function.h
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inline binder2nd<_Operation> bind2nd(const _Operation& __fn, const _Tp& __x) { typedef typename _Operation::second_argument_type _Arg2_type; return binder2nd<_Operation>(__fn, _Arg2_type(__x)); } /** @} */ // 20.3.7 adaptors pointers functions /** @defgroup s20_3_7_adaptors Adaptors for pointers to functions * The advantage of function objects over pointers to functions is that * the objects in the standard library declare nested typedefs describing * their argument and result types with uniform names (e.g., @c result_type * from the base classes @c unary_function and @c binary_function). * Sometimes those typedefs are required, not just optional. * * Adaptors are provided to turn pointers to unary (single-argument) and * binary (double-argument) functions into function objects. The * long-winded functor @c pointer_to_unary_function is constructed with a * function pointer @c f, and its @c operator() called with argument @c x * returns @c f(x). The functor @c pointer_to_binary_function does the same * thing, but with a double-argument @c f and @c operator(). * * The function @c ptr_fun takes a pointer-to-function @c f and constructs * an instance of the appropriate functor. * * @{ */ /// One of the @link s20_3_7_adaptors adaptors for function pointers@endlink. template <class _Arg, class _Result> class pointer_to_unary_function : public unary_function<_Arg, _Result> { protected: _Result (*_M_ptr)(_Arg); public: pointer_to_unary_function() {} explicit pointer_to_unary_function(_Result (*__x)(_Arg)) : _M_ptr(__x) {} _Result operator()(_Arg __x) const { return _M_ptr(__x); } }; /// One of the @link s20_3_7_adaptors adaptors for function pointers@endlink. template <class _Arg, class _Result> inline pointer_to_unary_function<_Arg, _Result> ptr_fun(_Result (*__x)(_Arg)) { return pointer_to_unary_function<_Arg, _Result>(__x); } /// One of the @link s20_3_7_adaptors adaptors for function pointers@endlink. template <class _Arg1, class _Arg2, class _Result> class pointer_to_binary_function : public binary_function<_Arg1, _Arg2, _Result> { protected: _Result (*_M_ptr)(_Arg1, _Arg2); public: pointer_to_binary_function() {} explicit pointer_to_binary_function(_Result (*__x)(_Arg1, _Arg2)) : _M_ptr(__x) {} _Result operator()(_Arg1 __x, _Arg2 __y) const { return _M_ptr(__x, __y); } }; /// One of the @link s20_3_7_adaptors adaptors for function pointers@endlink. template <class _Arg1, class _Arg2, class _Result> inline pointer_to_binary_function<_Arg1, _Arg2, _Result> ptr_fun(_Result (*__x)(_Arg1, _Arg2)) { return pointer_to_binary_function<_Arg1, _Arg2, _Result>(__x); } /** @} */ template <class _Tp> struct _Identity : public unary_function<_Tp,_Tp> { _Tp& operator()(_Tp& __x) const { return __x; } const _Tp& operator()(const _Tp& __x) const { return __x; } }; template <class _Pair> struct _Select1st : public unary_function<_Pair, typename _Pair::first_type> { typename _Pair::first_type& operator()(_Pair& __x) const { return __x.first; } const typename _Pair::first_type& operator()(const _Pair& __x) const { return __x.first; } }; template <class _Pair> struct _Select2nd : public unary_function<_Pair, typename _Pair::second_type> { typename _Pair::second_type& operator()(_Pair& __x) const { return __x.second; } const typename _Pair::second_type& operator()(const _Pair& __x) const { return __x.second; } }; // 20.3.8 adaptors pointers members /** @defgroup s20_3_8_memadaptors Adaptors for pointers to members * There are a total of 16 = 2^4 function objects in this family. * (1) Member functions taking no arguments vs member functions taking * one argument. * (2) Call through pointer vs call through reference. * (3) Member function with void return type vs member function with * non-void return type. * (4) Const vs non-const member function. * * Note that choice (3) is nothing more than a workaround: according * to the draft, compilers should handle void and non-void the same way. * This feature is not yet widely implemented, though. You can only use * member functions returning void if your compiler supports partial * specialization. * * All of this complexity is in the function objects themselves. You can * ignore it by using the helper function mem_fun and mem_fun_ref, * which create whichever type of adaptor is appropriate. * * @{ */ /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Ret, class _Tp> class mem_fun_t : public unary_function<_Tp*, _Ret> { public: explicit mem_fun_t(_Ret (_Tp::*__pf)()) : _M_f(__pf) {} _Ret operator()(_Tp* __p) const { return (__p->*_M_f)(); } private: _Ret (_Tp::*_M_f)(); }; /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Ret, class _Tp> class const_mem_fun_t : public unary_function<const _Tp*, _Ret> { public: explicit const_mem_fun_t(_Ret (_Tp::*__pf)() const) : _M_f(__pf) {} _Ret operator()(const _Tp* __p) const { return (__p->*_M_f)(); } private: _Ret (_Tp::*_M_f)() const; }; /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Ret, class _Tp> class mem_fun_ref_t : public unary_function<_Tp, _Ret> { public: explicit mem_fun_ref_t(_Ret (_Tp::*__pf)()) : _M_f(__pf) {} _Ret operator()(_Tp& __r) const { return (__r.*_M_f)(); } private: _Ret (_Tp::*_M_f)(); }; /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Ret, class _Tp> class const_mem_fun_ref_t : public unary_function<_Tp, _Ret> { public: explicit const_mem_fun_ref_t(_Ret (_Tp::*__pf)() const) : _M_f(__pf) {} _Ret operator()(const _Tp& __r) const { return (__r.*_M_f)(); } private: _Ret (_Tp::*_M_f)() const; }; /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Ret, class _Tp, class _Arg> class mem_fun1_t : public binary_function<_Tp*, _Arg, _Ret> { public: explicit mem_fun1_t(_Ret (_Tp::*__pf)(_Arg)) : _M_f(__pf) {} _Ret operator()(_Tp* __p, _Arg __x) const { return (__p->*_M_f)(__x); } private: _Ret (_Tp::*_M_f)(_Arg); }; /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Ret, class _Tp, class _Arg> class const_mem_fun1_t : public binary_function<const _Tp*, _Arg, _Ret> { public: explicit const_mem_fun1_t(_Ret (_Tp::*__pf)(_Arg) const) : _M_f(__pf) {} _Ret operator()(const _Tp* __p, _Arg __x) const { return (__p->*_M_f)(__x); } private: _Ret (_Tp::*_M_f)(_Arg) const; }; /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Ret, class _Tp, class _Arg> class mem_fun1_ref_t : public binary_function<_Tp, _Arg, _Ret> { public: explicit mem_fun1_ref_t(_Ret (_Tp::*__pf)(_Arg)) : _M_f(__pf) {} _Ret operator()(_Tp& __r, _Arg __x) const { return (__r.*_M_f)(__x); } private: _Ret (_Tp::*_M_f)(_Arg); }; /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Ret, class _Tp, class _Arg> class const_mem_fun1_ref_t : public binary_function<_Tp, _Arg, _Ret> { public: explicit const_mem_fun1_ref_t(_Ret (_Tp::*__pf)(_Arg) const) : _M_f(__pf) {} _Ret operator()(const _Tp& __r, _Arg __x) const { return (__r.*_M_f)(__x); } private: _Ret (_Tp::*_M_f)(_Arg) const; }; /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Tp> class mem_fun_t<void, _Tp> : public unary_function<_Tp*, void> { public: explicit mem_fun_t(void (_Tp::*__pf)()) : _M_f(__pf) {} void operator()(_Tp* __p) const { (__p->*_M_f)(); } private: void (_Tp::*_M_f)(); }; /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Tp> class const_mem_fun_t<void, _Tp> : public unary_function<const _Tp*, void> { public: explicit const_mem_fun_t(void (_Tp::*__pf)() const) : _M_f(__pf) {} void operator()(const _Tp* __p) const { (__p->*_M_f)(); } private: void (_Tp::*_M_f)() const; }; /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Tp> class mem_fun_ref_t<void, _Tp> : public unary_function<_Tp, void> { public: explicit mem_fun_ref_t(void (_Tp::*__pf)()) : _M_f(__pf) {} void operator()(_Tp& __r) const { (__r.*_M_f)(); } private: void (_Tp::*_M_f)(); }; /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Tp> class const_mem_fun_ref_t<void, _Tp> : public unary_function<_Tp, void> { public: explicit const_mem_fun_ref_t(void (_Tp::*__pf)() const) : _M_f(__pf) {} void operator()(const _Tp& __r) const { (__r.*_M_f)(); } private: void (_Tp::*_M_f)() const; }; /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Tp, class _Arg> class mem_fun1_t<void, _Tp, _Arg> : public binary_function<_Tp*, _Arg, void> { public: explicit mem_fun1_t(void (_Tp::*__pf)(_Arg)) : _M_f(__pf) {} void operator()(_Tp* __p, _Arg __x) const { (__p->*_M_f)(__x); } private: void (_Tp::*_M_f)(_Arg); }; /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Tp, class _Arg> class const_mem_fun1_t<void, _Tp, _Arg> : public binary_function<const _Tp*, _Arg, void> { public: explicit const_mem_fun1_t(void (_Tp::*__pf)(_Arg) const) : _M_f(__pf) {} void operator()(const _Tp* __p, _Arg __x) const { (__p->*_M_f)(__x); } private: void (_Tp::*_M_f)(_Arg) const; }; /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Tp, class _Arg> class mem_fun1_ref_t<void, _Tp, _Arg> : public binary_function<_Tp, _Arg, void> { public: explicit mem_fun1_ref_t(void (_Tp::*__pf)(_Arg)) : _M_f(__pf) {} void operator()(_Tp& __r, _Arg __x) const { (__r.*_M_f)(__x); } private: void (_Tp::*_M_f)(_Arg); }; /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink. template <class _Tp, class _Arg> class const_mem_fun1_ref_t<void, _Tp, _Arg> : public binary_function<_Tp, _Arg, void> { public: explicit const_mem_fun1_ref_t(void (_Tp::*__pf)(_Arg) const) : _M_f(__pf) {} void operator()(const _Tp& __r, _Arg __x) const { (__r.*_M_f)(__x); } private: void (_Tp::*_M_f)(_Arg) const; }; // Mem_fun adaptor helper functions. There are only two: // mem_fun and mem_fun_ref. template <class _Ret, class _Tp> inline mem_fun_t<_Ret, _Tp> mem_fun(_Ret (_Tp::*__f)()) { return mem_fun_t<_Ret, _Tp>(__f); } template <class _Ret, class _Tp> inline const_mem_fun_t<_Ret, _Tp> mem_fun(_Ret (_Tp::*__f)() const) { return const_mem_fun_t<_Ret, _Tp>(__f); } template <class _Ret, class _Tp> inline mem_fun_ref_t<_Ret, _Tp> mem_fun_ref(_Ret (_Tp::*__f)()) { return mem_fun_ref_t<_Ret, _Tp>(__f); } template <class _Ret, class _Tp> inline const_mem_fun_ref_t<_Ret, _Tp> mem_fun_ref(_Ret (_Tp::*__f)() const) { return const_mem_fun_ref_t<_Ret, _Tp>(__f); } template <class _Ret, class _Tp, class _Arg> inline mem_fun1_t<_Ret, _Tp, _Arg> mem_fun(_Ret (_Tp::*__f)(_Arg)) { return mem_fun1_t<_Ret, _Tp, _Arg>(__f); } template <class _Ret, class _Tp, class _Arg> inline const_mem_fun1_t<_Ret, _Tp, _Arg> mem_fun(_Ret (_Tp::*__f)(_Arg) const) { return const_mem_fun1_t<_Ret, _Tp, _Arg>(__f); } template <class _Ret, class _Tp, class _Arg> inline mem_fun1_ref_t<_Ret, _Tp, _Arg> mem_fun_ref(_Ret (_Tp::*__f)(_Arg)) { return mem_fun1_ref_t<_Ret, _Tp, _Arg>(__f); } template <class _Ret, class _Tp, class _Arg> inline const_mem_fun1_ref_t<_Ret, _Tp, _Arg> mem_fun_ref(_Ret (_Tp::*__f)(_Arg) const) { return const_mem_fun1_ref_t<_Ret, _Tp, _Arg>(__f); } /** @} */} // namespace std#endif /* _FUNCTION_H */// Local Variables:// mode:C++// End:
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