gcc/libstdc++-v3/include/tr1/functional
Benjamin Kosnik 2e8f8105a6 functional: Convert relative path.
2005-03-03  Benjamin Kosnik  <bkoz@redhat.com>

	* include/tr1/functional: Convert relative path.

	* docs/doxygen/user.cfg.in: Add tr1 includes.

From-SVN: r95838
2005-03-03 17:45:44 +00:00

924 lines
26 KiB
C++

// TR1 functional header -*- C++ -*-
// Copyright (C) 2004, 2005 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING. If not, write to the Free
// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
// USA.
// As a special exception, you may use this file as part of a free software
// library without restriction. Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License. This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.
/** @file
* This is a TR1 C++ Library header.
*/
#ifndef _TR1_FUNCTIONAL
#define _TR1_FUNCTIONAL 1
#include "../functional"
#include <typeinfo>
#include <tr1/type_traits>
#include <bits/cpp_type_traits.h>
#include <string> // for std::tr1::hash
#include <cstdlib> // for std::abort
namespace std
{
namespace tr1
{
template<typename _MemberPointer>
class _Mem_fn;
/**
* @if maint
* Actual implementation of _Has_result_type, which uses SFINAE to
* determine if the type _Tp has a publicly-accessible member type
* result_type.
* @endif
*/
template<typename _Tp>
class _Has_result_type_helper : __sfinae_types
{
template<typename _Up>
struct _Wrap_type
{ };
template<typename _Up>
static __one __test(_Wrap_type<typename _Up::result_type>*);
template<typename _Up>
static __two __test(...);
public:
static const bool value = sizeof(__test<_Tp>(0)) == 1;
};
template<typename _Tp>
struct _Has_result_type
: integral_constant<
bool,
_Has_result_type_helper<typename remove_cv<_Tp>::type>::value>
{ };
/**
* @if maint
* If we have found a result_type, extract it.
* @endif
*/
template<bool _Has_result_type, typename _Functor>
struct _Maybe_get_result_type
{ };
template<typename _Functor>
struct _Maybe_get_result_type<true, _Functor>
{
typedef typename _Functor::result_type result_type;
};
/**
* @if maint
* Base class for any function object that has a weak result type, as
* defined in 3.3/3 of TR1.
* @endif
*/
template<typename _Functor>
struct _Weak_result_type_impl
: _Maybe_get_result_type<_Has_result_type<_Functor>::value, _Functor>
{
};
/**
* @if maint
* Strip top-level cv-qualifiers from the function object and let
* _Weak_result_type_impl perform the real work.
* @endif
*/
template<typename _Functor>
struct _Weak_result_type
: _Weak_result_type_impl<typename remove_cv<_Functor>::type>
{
};
template<typename _Signature>
class result_of;
/**
* @if maint
* Actual implementation of result_of. When _Has_result_type is
* true, gets its result from _Weak_result_type. Otherwise, uses
* the function object's member template result to extract the
* result type.
* @endif
*/
template<bool _Has_result_type, typename _Signature>
struct _Result_of_impl;
// Handle member data pointers using _Mem_fn's logic
template<typename _Res, typename _Class, typename _T1>
struct _Result_of_impl<false, _Res _Class::*(_T1)>
{
typedef typename _Mem_fn<_Res _Class::*>
::template _Result_type<_T1>::type type;
};
/**
* @if maint
* Determines if the type _Tp derives from unary_function.
* @endif
*/
template<typename _Tp>
struct _Derives_from_unary_function : __sfinae_types
{
private:
template<typename _T1, typename _Res>
static __one __test(const volatile unary_function<_T1, _Res>*);
// It's tempting to change "..." to const volatile void*, but
// that fails when _Tp is a function type.
static __two __test(...);
public:
static const bool value = sizeof(__test((_Tp*)0)) == 1;
};
/**
* @if maint
* Determines if the type _Tp derives from binary_function.
* @endif
*/
template<typename _Tp>
struct _Derives_from_binary_function : __sfinae_types
{
private:
template<typename _T1, typename _T2, typename _Res>
static __one __test(const volatile binary_function<_T1, _T2, _Res>*);
// It's tempting to change "..." to const volatile void*, but
// that fails when _Tp is a function type.
static __two __test(...);
public:
static const bool value = sizeof(__test((_Tp*)0)) == 1;
};
/**
* @if maint
* Turns a function type into a function pointer type
* @endif
*/
template<typename _Tp, bool _IsFunctionType = is_function<_Tp>::value>
struct _Function_to_function_pointer
{
typedef _Tp type;
};
template<typename _Tp>
struct _Function_to_function_pointer<_Tp, true>
{
typedef _Tp* type;
};
/**
* @if maint
* Knowing which of unary_function and binary_function _Tp derives
* from, derives from the same and ensures that reference_wrapper
* will have a weak result type. See cases below.
* @endif
*/
template<bool _Unary, bool _Binary, typename _Tp>
struct _Reference_wrapper_base_impl;
// Not a unary_function or binary_function, so try a weak result type
template<typename _Tp>
struct _Reference_wrapper_base_impl<false, false, _Tp>
: _Weak_result_type<_Tp>
{ };
// unary_function but not binary_function
template<typename _Tp>
struct _Reference_wrapper_base_impl<true, false, _Tp>
: unary_function<typename _Tp::argument_type,
typename _Tp::result_type>
{ };
// binary_function but not unary_function
template<typename _Tp>
struct _Reference_wrapper_base_impl<false, true, _Tp>
: binary_function<typename _Tp::first_argument_type,
typename _Tp::second_argument_type,
typename _Tp::result_type>
{ };
// both unary_function and binary_function. import result_type to
// avoid conflicts.
template<typename _Tp>
struct _Reference_wrapper_base_impl<true, true, _Tp>
: unary_function<typename _Tp::argument_type,
typename _Tp::result_type>,
binary_function<typename _Tp::first_argument_type,
typename _Tp::second_argument_type,
typename _Tp::result_type>
{
typedef typename _Tp::result_type result_type;
};
/**
* @if maint
* Derives from unary_function or binary_function when it
* can. Specializations handle all of the easy cases. The primary
* template determines what to do with a class type, which may
* derive from both unary_function and binary_function.
* @endif
*/
template<typename _Tp>
struct _Reference_wrapper_base
: _Reference_wrapper_base_impl<
_Derives_from_unary_function<_Tp>::value,
_Derives_from_binary_function<_Tp>::value,
_Tp>
{ };
// - a function type (unary)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res(_T1)>
: unary_function<_T1, _Res>
{ };
// - a function type (binary)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res(_T1, _T2)>
: binary_function<_T1, _T2, _Res>
{ };
// - a function pointer type (unary)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res(*)(_T1)>
: unary_function<_T1, _Res>
{ };
// - a function pointer type (binary)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res(*)(_T1, _T2)>
: binary_function<_T1, _T2, _Res>
{ };
// - a pointer to member function type (unary, no qualifiers)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res (_T1::*)()>
: unary_function<_T1*, _Res>
{ };
// - a pointer to member function type (binary, no qualifiers)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res (_T1::*)(_T2)>
: binary_function<_T1*, _T2, _Res>
{ };
// - a pointer to member function type (unary, const)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res (_T1::*)() const>
: unary_function<const _T1*, _Res>
{ };
// - a pointer to member function type (binary, const)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res (_T1::*)(_T2) const>
: binary_function<const _T1*, _T2, _Res>
{ };
// - a pointer to member function type (unary, volatile)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res (_T1::*)() volatile>
: unary_function<volatile _T1*, _Res>
{ };
// - a pointer to member function type (binary, volatile)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res (_T1::*)(_T2) volatile>
: binary_function<volatile _T1*, _T2, _Res>
{ };
// - a pointer to member function type (unary, const volatile)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res (_T1::*)() const volatile>
: unary_function<const volatile _T1*, _Res>
{ };
// - a pointer to member function type (binary, const volatile)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res (_T1::*)(_T2) const volatile>
: binary_function<const volatile _T1*, _T2, _Res>
{ };
template<typename _Tp>
class reference_wrapper
: public _Reference_wrapper_base<typename remove_cv<_Tp>::type>
{
// If _Tp is a function type, we can't form result_of<_Tp(...)>,
// so turn it into a function pointer type.
typedef typename _Function_to_function_pointer<_Tp>::type
_M_func_type;
_Tp* _M_data;
public:
typedef _Tp type;
explicit reference_wrapper(_Tp& __indata): _M_data(&__indata)
{ }
reference_wrapper(const reference_wrapper<_Tp>& __inref):
_M_data(__inref._M_data)
{ }
reference_wrapper&
operator=(const reference_wrapper<_Tp>& __inref)
{
_M_data = __inref._M_data;
return *this;
}
operator _Tp&() const
{ return this->get(); }
_Tp&
get() const
{ return *_M_data; }
#define _GLIBCXX_REPEAT_HEADER <tr1/ref_wrap_iterate.h>
#include <tr1/repeat.h>
#undef _GLIBCXX_REPEAT_HEADER
};
// Denotes a reference should be taken to a variable.
template<typename _Tp>
reference_wrapper<_Tp>
ref(_Tp& __t)
{ return reference_wrapper<_Tp>(__t); }
// Denotes a const reference should be taken to a variable.
template<typename _Tp>
reference_wrapper<const _Tp>
cref(const _Tp& __t)
{ return reference_wrapper<const _Tp>(__t); }
template<typename _Tp>
reference_wrapper<_Tp> ref(reference_wrapper<_Tp> __t)
{ return ref(__t.get()); }
template<typename _Tp>
reference_wrapper<const _Tp> cref(reference_wrapper<_Tp> __t)
{ return cref(__t.get()); }
template<typename _Tp, bool>
struct _Mem_fn_const_or_non
{
typedef const _Tp& type;
};
template<typename _Tp>
struct _Mem_fn_const_or_non<_Tp, false>
{
typedef _Tp& type;
};
template<typename _Res, typename _Class>
class _Mem_fn<_Res _Class::*>
{
// This bit of genius is due to Peter Dimov, improved slightly by
// Douglas Gregor.
template<typename _Tp>
_Res&
_M_call(_Tp& __object, _Class *) const
{ return __object.*__pm; }
template<typename _Tp, typename _Up>
_Res&
_M_call(_Tp& __object, _Up * const *) const
{ return (*__object).*__pm; }
template<typename _Tp, typename _Up>
const _Res&
_M_call(_Tp& __object, const _Up * const *) const
{ return (*__object).*__pm; }
template<typename _Tp>
const _Res&
_M_call(_Tp& __object, const _Class *) const
{ return __object.*__pm; }
template<typename _Tp>
const _Res&
_M_call(_Tp& __ptr, const volatile void*) const
{ return (*__ptr).*__pm; }
template<typename _Tp> static _Tp& __get_ref();
template<typename _Tp>
static __sfinae_types::__one __check_const(_Tp&, _Class*);
template<typename _Tp, typename _Up>
static __sfinae_types::__one __check_const(_Tp&, _Up * const *);
template<typename _Tp, typename _Up>
static __sfinae_types::__two __check_const(_Tp&, const _Up * const *);
template<typename _Tp>
static __sfinae_types::__two __check_const(_Tp&, const _Class*);
template<typename _Tp>
static __sfinae_types::__two __check_const(_Tp&, const volatile void*);
public:
template<typename _Tp>
struct _Result_type
: _Mem_fn_const_or_non<
_Res,
(sizeof(__sfinae_types::__two)
== sizeof(__check_const<_Tp>(__get_ref<_Tp>(), (_Tp*)0)))>
{ };
explicit _Mem_fn(_Res _Class::*__pm) : __pm(__pm) { }
// Handle objects
_Res& operator()(_Class& __object) const
{ return __object.*__pm; }
const _Res& operator()(const _Class& __object) const
{ return __object.*__pm; }
// Handle pointers
_Res& operator()(_Class* __object) const
{ return __object->*__pm; }
const _Res&
operator()(const _Class* __object) const
{ return __object->*__pm; }
// Handle smart pointers and derived
template<typename _Tp>
typename _Result_type<_Tp>::type
operator()(_Tp& __unknown) const
{ return _M_call(__unknown, &__unknown); }
private:
_Res _Class::*__pm;
};
/**
* @brief Returns a function object that forwards to the member
* pointer @a pm.
*/
template<typename _Tp, typename _Class>
inline _Mem_fn<_Tp _Class::*>
mem_fn(_Tp _Class::* __pm)
{
return _Mem_fn<_Tp _Class::*>(__pm);
}
/**
* @brief Exception class thrown when class template function's
* operator() is called with an empty target.
*
*/
class bad_function_call : public std::exception { };
/**
* @if maint
* The integral constant expression 0 can be converted into a
* pointer to this type. It is used by the function template to
* accept NULL pointers.
* @endif
*/
struct _M_clear_type;
/**
* @if maint
* Trait identifying "location-invariant" types, meaning that the
* address of the object (or any of its members) will not escape.
* Also implies a trivial copy constructor and assignment operator.
* @endif
*/
template<typename _Tp>
struct __is_location_invariant
: integral_constant<bool,
(is_pointer<_Tp>::value
|| is_member_pointer<_Tp>::value)>
{
};
class _Undefined_class;
union _Nocopy_types
{
void* _M_object;
const void* _M_const_object;
void (*_M_function_pointer)();
void (_Undefined_class::*_M_member_pointer)();
};
union _Any_data {
void* _M_access() { return &_M_pod_data[0]; }
const void* _M_access() const { return &_M_pod_data[0]; }
template<typename _Tp> _Tp& _M_access()
{ return *static_cast<_Tp*>(_M_access()); }
template<typename _Tp> const _Tp& _M_access() const
{ return *static_cast<const _Tp*>(_M_access()); }
_Nocopy_types _M_unused;
char _M_pod_data[sizeof(_Nocopy_types)];
};
enum _Manager_operation
{
__get_type_info,
__get_functor_ptr,
__clone_functor,
__destroy_functor
};
/* Simple type wrapper that helps avoid annoying const problems
when casting between void pointers and pointers-to-pointers. */
template<typename _Tp>
struct _Simple_type_wrapper
{
_Simple_type_wrapper(_Tp __value) : __value(__value) { }
_Tp __value;
};
template<typename _Tp>
struct __is_location_invariant<_Simple_type_wrapper<_Tp> >
: __is_location_invariant<_Tp>
{
};
// Converts a reference to a function object into a callable
// function object.
template<typename _Functor>
inline _Functor& __callable_functor(_Functor& __f) { return __f; }
template<typename _Member, typename _Class>
inline _Mem_fn<_Member _Class::*>
__callable_functor(_Member _Class::* &__p)
{ return mem_fn(__p); }
template<typename _Member, typename _Class>
inline _Mem_fn<_Member _Class::*>
__callable_functor(_Member _Class::* const &__p)
{ return mem_fn(__p); }
template<typename _Signature, typename _Functor>
class _Function_handler;
template<typename _Signature>
class function;
/**
* @if maint
* Base class of all polymorphic function object wrappers.
* @endif
*/
class _Function_base
{
public:
static const std::size_t _M_max_size = sizeof(_Nocopy_types);
static const std::size_t _M_max_align = __alignof__(_Nocopy_types);
template<typename _Functor>
class _Base_manager
{
protected:
static const bool __stored_locally =
(__is_location_invariant<_Functor>::value
&& sizeof(_Functor) <= _M_max_size
&& __alignof__(_Functor) <= _M_max_align
&& (_M_max_align % __alignof__(_Functor) == 0));
typedef integral_constant<bool, __stored_locally> _Local_storage;
// Retrieve a pointer to the function object
static _Functor* _M_get_pointer(const _Any_data& __source)
{
const _Functor* __ptr =
__stored_locally? &__source._M_access<_Functor>()
/* have stored a pointer */ : __source._M_access<_Functor*>();
return const_cast<_Functor*>(__ptr);
}
// Clone a location-invariant function object that fits within
// an _Any_data structure.
static void
_M_clone(_Any_data& __dest, const _Any_data& __source, true_type)
{
new (__dest._M_access()) _Functor(__source._M_access<_Functor>());
}
// Clone a function object that is not location-invariant or
// that cannot fit into an _Any_data structure.
static void
_M_clone(_Any_data& __dest, const _Any_data& __source, false_type)
{
__dest._M_access<_Functor*>() =
new _Functor(*__source._M_access<_Functor*>());
}
// Destroying a location-invariant object may still require
// destruction.
static void
_M_destroy(_Any_data& __victim, true_type)
{
__victim._M_access<_Functor>().~_Functor();
}
// Destroying an object located on the heap.
static void
_M_destroy(_Any_data& __victim, false_type)
{
delete __victim._M_access<_Functor*>();
}
public:
static bool
_M_manager(_Any_data& __dest, const _Any_data& __source,
_Manager_operation __op)
{
switch (__op) {
case __get_type_info:
__dest._M_access<const type_info*>() = &typeid(_Functor);
break;
case __get_functor_ptr:
__dest._M_access<_Functor*>() = _M_get_pointer(__source);
break;
case __clone_functor:
_M_clone(__dest, __source, _Local_storage());
break;
case __destroy_functor:
_M_destroy(__dest, _Local_storage());
break;
}
return false;
}
static void
_M_init_functor(_Any_data& __functor, const _Functor& __f)
{
_M_init_functor(__functor, __f, _Local_storage());
}
template<typename _Signature>
static bool
_M_not_empty_function(const function<_Signature>& __f)
{
return __f;
}
template<typename _Tp>
static bool
_M_not_empty_function(const _Tp*& __fp)
{
return __fp;
}
template<typename _Class, typename _Tp>
static bool
_M_not_empty_function(_Tp _Class::* const& __mp)
{
return __mp;
}
template<typename _Tp>
static bool
_M_not_empty_function(const _Tp&)
{
return true;
}
private:
static void
_M_init_functor(_Any_data& __functor, const _Functor& __f, true_type)
{
new (__functor._M_access()) _Functor(__f);
}
static void
_M_init_functor(_Any_data& __functor, const _Functor& __f, false_type)
{
__functor._M_access<_Functor*>() = new _Functor(__f);
}
};
template<typename _Functor>
class _Ref_manager : public _Base_manager<_Functor*>
{
typedef _Function_base::_Base_manager<_Functor*> _Base;
public:
static bool
_M_manager(_Any_data& __dest, const _Any_data& __source,
_Manager_operation __op)
{
switch (__op) {
case __get_type_info:
__dest._M_access<const type_info*>() = &typeid(_Functor);
break;
case __get_functor_ptr:
__dest._M_access<_Functor*>() = *_Base::_M_get_pointer(__source);
return is_const<_Functor>::value;
break;
default:
_Base::_M_manager(__dest, __source, __op);
}
return false;
}
static void
_M_init_functor(_Any_data& __functor, reference_wrapper<_Functor> __f)
{
// TBD: Use address_of function instead
_Base::_M_init_functor(__functor, &__f.get());
}
};
_Function_base() : _M_manager(0) { }
~_Function_base()
{
if (_M_manager)
{
_M_manager(_M_functor, _M_functor, __destroy_functor);
}
}
bool _M_empty() const { return !_M_manager; }
typedef bool (*_Manager_type)(_Any_data&, const _Any_data&,
_Manager_operation);
_Any_data _M_functor;
_Manager_type _M_manager;
};
// [3.7.2.7] null pointer comparisons
/**
* @brief Compares a polymorphic function object wrapper against 0
* (the NULL pointer).
* @returns @c true if the wrapper has no target, @c false otherwise
*
* This function will not throw an exception.
*/
template<typename _Signature>
inline bool
operator==(const function<_Signature>& __f, _M_clear_type*)
{
return !__f;
}
/**
* @overload
*/
template<typename _Signature>
inline bool
operator==(_M_clear_type*, const function<_Signature>& __f)
{
return !__f;
}
/**
* @brief Compares a polymorphic function object wrapper against 0
* (the NULL pointer).
* @returns @c false if the wrapper has no target, @c true otherwise
*
* This function will not throw an exception.
*/
template<typename _Signature>
inline bool
operator!=(const function<_Signature>& __f, _M_clear_type*)
{
return __f;
}
/**
* @overload
*/
template<typename _Signature>
inline bool
operator!=(_M_clear_type*, const function<_Signature>& __f)
{
return __f;
}
// [3.7.2.8] specialized algorithms
/**
* @brief Swap the targets of two polymorphic function object wrappers.
*
* This function will not throw an exception.
*/
template<typename _Signature>
inline void
swap(function<_Signature>& __x, function<_Signature>& __y)
{
__x.swap(__y);
}
#define _GLIBCXX_REPEAT_HEADER <tr1/functional_iterate.h>
#include <tr1/repeat.h>
#undef _GLIBCXX_REPEAT_HEADER
// Definition of default hash function std::tr1::hash<>. The types for
// which std::tr1::hash<T> is defined is in clause 6.3.3. of the PDTR.
template <typename T> struct hash;
#define tr1_hashtable_define_trivial_hash(T) \
template <> struct hash<T> { \
std::size_t operator()(T val) const { return static_cast<std::size_t>(val); } \
} \
tr1_hashtable_define_trivial_hash(bool);
tr1_hashtable_define_trivial_hash(char);
tr1_hashtable_define_trivial_hash(signed char);
tr1_hashtable_define_trivial_hash(unsigned char);
tr1_hashtable_define_trivial_hash(wchar_t);
tr1_hashtable_define_trivial_hash(short);
tr1_hashtable_define_trivial_hash(int);
tr1_hashtable_define_trivial_hash(long);
tr1_hashtable_define_trivial_hash(unsigned short);
tr1_hashtable_define_trivial_hash(unsigned int);
tr1_hashtable_define_trivial_hash(unsigned long);
tr1_hashtable_define_trivial_hash(float);
tr1_hashtable_define_trivial_hash(double);
tr1_hashtable_define_trivial_hash(long double);
#undef tr1_hashtable_define_trivial_hash
template <typename T>
struct hash<T*> {
std::size_t operator()(T* p) const {
return reinterpret_cast<std::size_t>(p);
}
};
// ??? We can probably find a better hash function than this (i.e. one
// that vectorizes better and that produces a more uniform distribution).
// XXX String hash probably shouldn't be an inline member function,
// since it's nontrivial. Once we have the framework for TR1 .cc
// files, this should go in one.
template <>
struct hash<std::string>
{
std::size_t operator()(const std::string& s) const
{
std::size_t result = 0;
for (std::string::const_iterator i = s.begin(); i != s.end(); ++i)
result = (result * 131) + *i;
return result;
}
};
#ifdef _GLIBCXX_USE_WCHAR_T
template <>
struct hash<std::wstring>
{
std::size_t operator()(const std::wstring& s) const
{
std::size_t result = 0;
for (std::wstring::const_iterator i = s.begin(); i != s.end(); ++i)
result = (result * 131) + *i;
return result;
}
};
#endif
}
}
#endif