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gcc/libstdc++-v3/include/std/std_bitset.h
Phil Edwards e92a4045ac std_bitset.h: Fix doxygen comments. 
2002-05-01  Phil Edwards  <pme@gcc.gnu.org>

	* include/std/std_bitset.h:  Fix doxygen comments.
	* docs/html/documentation.html:  Minor tweaks for 3.1.
	* docs/html/27_io/howto.html:  Likewise.
	* docs/html/ext/howto.html:  Likewise, mention stdio_filebuf.
	* docs/html/faq/index.html:  Likewise.
	* docs/html/faq/index.txt:  Regenerated.

From-SVN: r53025
2002-05-01 22:57:59 +00:00

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// <bitset> -*- C++ -*-
// Copyright (C) 2001, 2002 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.
/*
* Copyright (c) 1998
* Silicon Graphics Computer Systems, Inc.
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Silicon Graphics makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*/
/** @file bitset
* This is a Standard C++ Library header. You should @c #include this header
* in your programs, rather than any of the "st[dl]_*.h" implementation files.
*/
#ifndef _GLIBCPP_BITSET_H
#define _GLIBCPP_BITSET_H
#pragma GCC system_header
#include <cstddef> // for size_t
#include <cstring> // for memset
#include <string>
#include <bits/functexcept.h> // for invalid_argument, out_of_range,
// overflow_error
#include <ostream> // for ostream (operator<<)
#include <istream> // for istream (operator>>)
#define _GLIBCPP_BITSET_BITS_PER_WORD (CHAR_BIT*sizeof(unsigned long))
#define _GLIBCPP_BITSET_WORDS(__n) \
((__n) < 1 ? 1 : ((__n) + _GLIBCPP_BITSET_BITS_PER_WORD - 1)/_GLIBCPP_BITSET_BITS_PER_WORD)
namespace std
{
extern unsigned char _S_bit_count[256];
extern unsigned char _S_first_one[256];
/**
* @if maint
* Base class, general case. It is a class inveriant that _Nw will be
* nonnegative.
*
* See documentation for bitset.
* @endif
*/
template<size_t _Nw>
struct _Base_bitset
{
typedef unsigned long _WordT;
/// 0 is the least significant word.
_WordT _M_w[_Nw];
_Base_bitset() { _M_do_reset(); }
_Base_bitset(unsigned long __val)
{
_M_do_reset();
_M_w[0] = __val;
}
static size_t
_S_whichword(size_t __pos )
{ return __pos / _GLIBCPP_BITSET_BITS_PER_WORD; }
static size_t
_S_whichbyte(size_t __pos )
{ return (__pos % _GLIBCPP_BITSET_BITS_PER_WORD) / CHAR_BIT; }
static size_t
_S_whichbit(size_t __pos )
{ return __pos % _GLIBCPP_BITSET_BITS_PER_WORD; }
static _WordT
_S_maskbit(size_t __pos )
{ return (static_cast<_WordT>(1)) << _S_whichbit(__pos); }
_WordT&
_M_getword(size_t __pos)
{ return _M_w[_S_whichword(__pos)]; }
_WordT
_M_getword(size_t __pos) const
{ return _M_w[_S_whichword(__pos)]; }
_WordT&
_M_hiword() { return _M_w[_Nw - 1]; }
_WordT
_M_hiword() const { return _M_w[_Nw - 1]; }
void
_M_do_and(const _Base_bitset<_Nw>& __x)
{
for (size_t __i = 0; __i < _Nw; __i++)
_M_w[__i] &= __x._M_w[__i];
}
void
_M_do_or(const _Base_bitset<_Nw>& __x)
{
for (size_t __i = 0; __i < _Nw; __i++)
_M_w[__i] |= __x._M_w[__i];
}
void
_M_do_xor(const _Base_bitset<_Nw>& __x)
{
for (size_t __i = 0; __i < _Nw; __i++)
_M_w[__i] ^= __x._M_w[__i];
}
void
_M_do_left_shift(size_t __shift);
void
_M_do_right_shift(size_t __shift);
void
_M_do_flip()
{
for (size_t __i = 0; __i < _Nw; __i++)
_M_w[__i] = ~_M_w[__i];
}
void
_M_do_set()
{
for (size_t __i = 0; __i < _Nw; __i++)
_M_w[__i] = ~static_cast<_WordT>(0);
}
void
_M_do_reset() { memset(_M_w, 0, _Nw * sizeof(_WordT)); }
bool
_M_is_equal(const _Base_bitset<_Nw>& __x) const
{
for (size_t __i = 0; __i < _Nw; ++__i)
{
if (_M_w[__i] != __x._M_w[__i])
return false;
}
return true;
}
bool
_M_is_any() const
{
for (size_t __i = 0; __i < _Nw; __i++)
{
if (_M_w[__i] != static_cast<_WordT>(0))
return true;
}
return false;
}
size_t
_M_do_count() const
{
size_t __result = 0;
const unsigned char* __byte_ptr = (const unsigned char*)_M_w;
const unsigned char* __end_ptr = (const unsigned char*)(_M_w + _Nw);
while ( __byte_ptr < __end_ptr )
{
__result += _S_bit_count[*__byte_ptr];
__byte_ptr++;
}
return __result;
}
unsigned long
_M_do_to_ulong() const;
// find first "on" bit
size_t
_M_do_find_first(size_t __not_found) const;
// find the next "on" bit that follows "prev"
size_t
_M_do_find_next(size_t __prev, size_t __not_found) const;
};
// Definitions of non-inline functions from _Base_bitset.
template<size_t _Nw>
void
_Base_bitset<_Nw>::_M_do_left_shift(size_t __shift)
{
if (__shift != 0)
{
const size_t __wshift = __shift / _GLIBCPP_BITSET_BITS_PER_WORD;
const size_t __offset = __shift % _GLIBCPP_BITSET_BITS_PER_WORD;
if (__offset == 0)
for (size_t __n = _Nw - 1; __n >= __wshift; --__n)
_M_w[__n] = _M_w[__n - __wshift];
else
{
const size_t __sub_offset = _GLIBCPP_BITSET_BITS_PER_WORD - __offset;
for (size_t __n = _Nw - 1; __n > __wshift; --__n)
_M_w[__n] = (_M_w[__n - __wshift] << __offset) |
(_M_w[__n - __wshift - 1] >> __sub_offset);
_M_w[__wshift] = _M_w[0] << __offset;
}
fill(_M_w + 0, _M_w + __wshift, static_cast<_WordT>(0));
}
}
template<size_t _Nw>
void
_Base_bitset<_Nw>::_M_do_right_shift(size_t __shift)
{
if (__shift != 0)
{
const size_t __wshift = __shift / _GLIBCPP_BITSET_BITS_PER_WORD;
const size_t __offset = __shift % _GLIBCPP_BITSET_BITS_PER_WORD;
const size_t __limit = _Nw - __wshift - 1;
if (__offset == 0)
for (size_t __n = 0; __n <= __limit; ++__n)
_M_w[__n] = _M_w[__n + __wshift];
else
{
const size_t __sub_offset = _GLIBCPP_BITSET_BITS_PER_WORD - __offset;
for (size_t __n = 0; __n < __limit; ++__n)
_M_w[__n] = (_M_w[__n + __wshift] >> __offset) |
(_M_w[__n + __wshift + 1] << __sub_offset);
_M_w[__limit] = _M_w[_Nw-1] >> __offset;
}
fill(_M_w + __limit + 1, _M_w + _Nw, static_cast<_WordT>(0));
}
}
template<size_t _Nw>
unsigned long
_Base_bitset<_Nw>::_M_do_to_ulong() const
{
for (size_t __i = 1; __i < _Nw; ++__i)
if (_M_w[__i])
__throw_overflow_error("bitset -- too large to fit in unsigned long");
return _M_w[0];
}
template<size_t _Nw>
size_t
_Base_bitset<_Nw>::_M_do_find_first(size_t __not_found) const
{
for (size_t __i = 0; __i < _Nw; __i++ )
{
_WordT __thisword = _M_w[__i];
if ( __thisword != static_cast<_WordT>(0) )
{
// find byte within word
for (size_t __j = 0; __j < sizeof(_WordT); __j++ )
{
unsigned char __this_byte
= static_cast<unsigned char>(__thisword & (~(unsigned char)0));
if (__this_byte)
return __i*_GLIBCPP_BITSET_BITS_PER_WORD + __j*CHAR_BIT +
_S_first_one[__this_byte];
__thisword >>= CHAR_BIT;
}
}
}
// not found, so return an indication of failure.
return __not_found;
}
template<size_t _Nw>
size_t
_Base_bitset<_Nw>::_M_do_find_next(size_t __prev, size_t __not_found) const
{
// make bound inclusive
++__prev;
// check out of bounds
if ( __prev >= _Nw * _GLIBCPP_BITSET_BITS_PER_WORD )
return __not_found;
// search first word
size_t __i = _S_whichword(__prev);
_WordT __thisword = _M_w[__i];
// mask off bits below bound
__thisword &= (~static_cast<_WordT>(0)) << _S_whichbit(__prev);
if ( __thisword != static_cast<_WordT>(0) )
{
// find byte within word
// get first byte into place
__thisword >>= _S_whichbyte(__prev) * CHAR_BIT;
for (size_t __j = _S_whichbyte(__prev); __j < sizeof(_WordT); __j++)
{
unsigned char __this_byte
= static_cast<unsigned char>(__thisword & (~(unsigned char)0));
if ( __this_byte )
return __i*_GLIBCPP_BITSET_BITS_PER_WORD + __j*CHAR_BIT +
_S_first_one[__this_byte];
__thisword >>= CHAR_BIT;
}
}
// check subsequent words
__i++;
for ( ; __i < _Nw; __i++ )
{
__thisword = _M_w[__i];
if ( __thisword != static_cast<_WordT>(0) )
{
// find byte within word
for (size_t __j = 0; __j < sizeof(_WordT); __j++ )
{
unsigned char __this_byte
= static_cast<unsigned char>(__thisword & (~(unsigned char)0));
if ( __this_byte )
return __i*_GLIBCPP_BITSET_BITS_PER_WORD + __j*CHAR_BIT +
_S_first_one[__this_byte];
__thisword >>= CHAR_BIT;
}
}
}
// not found, so return an indication of failure.
return __not_found;
} // end _M_do_find_next
/**
* @if maint
* Base class, specialization for a single word.
*
* See documentation for bitset.
* @endif
*/
template<>
struct _Base_bitset<1>
{
typedef unsigned long _WordT;
_WordT _M_w;
_Base_bitset( void ) : _M_w(0) {}
_Base_bitset(unsigned long __val) : _M_w(__val) {}
static size_t
_S_whichword(size_t __pos )
{ return __pos / _GLIBCPP_BITSET_BITS_PER_WORD; }
static size_t
_S_whichbyte(size_t __pos )
{ return (__pos % _GLIBCPP_BITSET_BITS_PER_WORD) / CHAR_BIT; }
static size_t
_S_whichbit(size_t __pos )
{ return __pos % _GLIBCPP_BITSET_BITS_PER_WORD; }
static _WordT
_S_maskbit(size_t __pos )
{ return (static_cast<_WordT>(1)) << _S_whichbit(__pos); }
_WordT&
_M_getword(size_t) { return _M_w; }
_WordT
_M_getword(size_t) const { return _M_w; }
_WordT&
_M_hiword() { return _M_w; }
_WordT
_M_hiword() const { return _M_w; }
void
_M_do_and(const _Base_bitset<1>& __x) { _M_w &= __x._M_w; }
void
_M_do_or(const _Base_bitset<1>& __x) { _M_w |= __x._M_w; }
void
_M_do_xor(const _Base_bitset<1>& __x) { _M_w ^= __x._M_w; }
void
_M_do_left_shift(size_t __shift) { _M_w <<= __shift; }
void
_M_do_right_shift(size_t __shift) { _M_w >>= __shift; }
void
_M_do_flip() { _M_w = ~_M_w; }
void
_M_do_set() { _M_w = ~static_cast<_WordT>(0); }
void
_M_do_reset() { _M_w = 0; }
bool
_M_is_equal(const _Base_bitset<1>& __x) const
{ return _M_w == __x._M_w; }
bool
_M_is_any() const { return _M_w != 0; }
size_t
_M_do_count() const
{
size_t __result = 0;
const unsigned char* __byte_ptr = (const unsigned char*)&_M_w;
const unsigned char* __end_ptr
= ((const unsigned char*)&_M_w)+sizeof(_M_w);
while ( __byte_ptr < __end_ptr )
{
__result += _S_bit_count[*__byte_ptr];
__byte_ptr++;
}
return __result;
}
unsigned long
_M_do_to_ulong() const { return _M_w; }
size_t
_M_do_find_first(size_t __not_found) const;
// find the next "on" bit that follows "prev"
size_t
_M_do_find_next(size_t __prev, size_t __not_found) const;
};
// Helper class to zero out the unused high-order bits in the highest word.
template<size_t _Extrabits>
struct _Sanitize
{
static void _S_do_sanitize(unsigned long& __val)
{ __val &= ~((~static_cast<unsigned long>(0)) << _Extrabits); }
};
template<>
struct _Sanitize<0>
{ static void _S_do_sanitize(unsigned long) { } };
/**
* @brief The %bitset class represents a @e fixed-size sequence of bits.
*
* @ingroup Containers
*
* (Note that %bitset does @e not meet the formal requirements of a
* <a href="tables.html#65">container</a>. Mainly, it lacks iterators.)
*
* The template argument, @a _Nb, may be any nonzero number of type
* size_t.
*
* A %bitset of size N has N % (sizeof(unsigned long) * CHAR_BIT) unused
* bits. (They are the high-order bits in the highest word.) It is
* a class invariant that those unused bits are always zero.
*
* If you think of %bitset as "a simple array of bits," be aware that
* your mental picture is reversed: a %bitset behaves the same way as
* bits in integers do, with the bit at index 0 in the "least significant
* / right-hand" position, and the bit at index N-1 in the "most
* significant / left-hand" position. Thus, unlike other containers, a
* %bitset's index "counts from right to left," to put it very loosely.
*
* This behavior is preserved when translating to and from strings. For
* example, the first line of the following program probably prints
* "b('a') is 0001100001" on a modern ASCII system.
*
* @code
* #include <bitset>
* #include <iostream>
* #include <sstream>
*
* using namespace std;
*
* int main()
* {
* long a = 'a';
* bitset<10> b(a);
*
* cout << "b('a') is " << b << endl;
*
* ostringstream s;
* s << b;
* string str = s.str();
* cout << "index 3 in the string is " << str[3] << " but\n"
* << "index 3 in the bitset is " << b[3] << endl;
* }
* @endcode
*
* Also see http://gcc.gnu.org/onlinedocs/libstdc++/ext/sgiexts.html#ch23
*
* @if maint
* Most of the actual code isn't contained in %bitset<> itself, but in the
* base class _Base_bitset. The base class works with whole words, not with
* individual bits. This allows us to specialize _Base_bitset for the
* important special case where the %bitset is only a single word.
*
* Extra confusion can result due to the fact that the storage for
* _Base_bitset @e is a regular array, and is indexed as such. This is
* carefully encapsulated.
* @endif
*/
template<size_t _Nb>
class bitset : private _Base_bitset<_GLIBCPP_BITSET_WORDS(_Nb)>
{
private:
typedef _Base_bitset<_GLIBCPP_BITSET_WORDS(_Nb)> _Base;
typedef unsigned long _WordT;
void
_M_do_sanitize()
{
_Sanitize<_Nb%_GLIBCPP_BITSET_BITS_PER_WORD>::
_S_do_sanitize(this->_M_hiword());
}
public:
/**
* This encapsulates the concept of a single bit. An instance of this
* class is a proxy for an actual bit; this way the individual bit
* operations are done as faster word-size bitwise instructions.
*
* Most users will never need to use this class directly; conversions
* to and from bool are automatic and should be transparent. Overloaded
* operators help to preserve the illusion.
*
* (On a typical system, this "bit %reference" is 64 times the size of
* an actual bit. Ha.)
*/
class reference
{
friend class bitset;
_WordT *_M_wp;
size_t _M_bpos;
// left undefined
reference();
public:
reference(bitset& __b, size_t __pos)
{
_M_wp = &__b._M_getword(__pos);
_M_bpos = _Base::_S_whichbit(__pos);
}
~reference() { }
// for b[i] = __x;
reference&
operator=(bool __x)
{
if ( __x )
*_M_wp |= _Base::_S_maskbit(_M_bpos);
else
*_M_wp &= ~_Base::_S_maskbit(_M_bpos);
return *this;
}
// for b[i] = b[__j];
reference&
operator=(const reference& __j)
{
if ( (*(__j._M_wp) & _Base::_S_maskbit(__j._M_bpos)) )
*_M_wp |= _Base::_S_maskbit(_M_bpos);
else
*_M_wp &= ~_Base::_S_maskbit(_M_bpos);
return *this;
}
// flips the bit
bool
operator~() const
{ return (*(_M_wp) & _Base::_S_maskbit(_M_bpos)) == 0; }
// for __x = b[i];
operator bool() const
{ return (*(_M_wp) & _Base::_S_maskbit(_M_bpos)) != 0; }
// for b[i].flip();
reference&
flip()
{
*_M_wp ^= _Base::_S_maskbit(_M_bpos);
return *this;
}
};
friend class reference;
// 23.3.5.1 constructors:
/// All bits set to zero.
bitset() { }
/// Initial bits bitwise-copied from a single word (others set to zero).
bitset(unsigned long __val) : _Base(__val)
{ _M_do_sanitize(); }
/**
* @brief Use a subset of a string.
* @param s A string of '0' and '1' characters.
* @param pos Index of the first character in @a s to use; defaults
* to zero.
* @throw std::out_of_range If @a pos is bigger the size of @a s.
* @throw std::invalid_argument If a character appears in the string
* which is neither '0' nor '1'.
*/
template<class _CharT, class _Traits, class _Alloc>
explicit bitset(const basic_string<_CharT, _Traits, _Alloc>& __s,
size_t __pos = 0) : _Base()
{
if (__pos > __s.size())
__throw_out_of_range("bitset -- initial position is larger than "
"the string itself");
_M_copy_from_string(__s, __pos,
basic_string<_CharT, _Traits, _Alloc>::npos);
}
/**
* @brief Use a subset of a string.
* @param s A string of '0' and '1' characters.
* @param pos Index of the first character in @a s to use.
* @param n The number of characters to copy.
* @throw std::out_of_range If @a pos is bigger the size of @a s.
* @throw std::invalid_argument If a character appears in the string
* which is neither '0' nor '1'.
*/
template<class _CharT, class _Traits, class _Alloc>
bitset(const basic_string<_CharT, _Traits, _Alloc>& __s,
size_t __pos, size_t __n) : _Base()
{
if (__pos > __s.size())
__throw_out_of_range("bitset -- initial position is larger than "
"the string itself");
_M_copy_from_string(__s, __pos, __n);
}
// 23.3.5.2 bitset operations:
//@{
/**
* @brief Operations on bitsets.
* @param rhs A same-sized bitset.
*
* These should be self-explanatory.
*/
bitset<_Nb>&
operator&=(const bitset<_Nb>& __rhs)
{
this->_M_do_and(__rhs);
return *this;
}
bitset<_Nb>&
operator|=(const bitset<_Nb>& __rhs)
{
this->_M_do_or(__rhs);
return *this;
}
bitset<_Nb>&
operator^=(const bitset<_Nb>& __rhs)
{
this->_M_do_xor(__rhs);
return *this;
}
//@}
//@{
/**
* @brief Operations on bitsets.
* @param pos The number of places to shift.
*
* These should be self-explanatory.
*/
bitset<_Nb>&
operator<<=(size_t __pos)
{
this->_M_do_left_shift(__pos);
this->_M_do_sanitize();
return *this;
}
bitset<_Nb>&
operator>>=(size_t __pos)
{
this->_M_do_right_shift(__pos);
this->_M_do_sanitize();
return *this;
}
//@}
//@{
/**
* These versions of single-bit set, reset, flip, and test are
* extensions from the SGI version. They do no range checking.
* @ingroup SGIextensions
*/
bitset<_Nb>&
_Unchecked_set(size_t __pos)
{
this->_M_getword(__pos) |= _Base::_S_maskbit(__pos);
return *this;
}
bitset<_Nb>&
_Unchecked_set(size_t __pos, int __val)
{
if (__val)
this->_M_getword(__pos) |= _Base::_S_maskbit(__pos);
else
this->_M_getword(__pos) &= ~_Base::_S_maskbit(__pos);
return *this;
}
bitset<_Nb>&
_Unchecked_reset(size_t __pos)
{
this->_M_getword(__pos) &= ~_Base::_S_maskbit(__pos);
return *this;
}
bitset<_Nb>&
_Unchecked_flip(size_t __pos)
{
this->_M_getword(__pos) ^= _Base::_S_maskbit(__pos);
return *this;
}
bool
_Unchecked_test(size_t __pos) const
{
return (this->_M_getword(__pos) & _Base::_S_maskbit(__pos))
!= static_cast<_WordT>(0);
}
//@}
// Set, reset, and flip.
/**
* @brief Sets every bit to true.
*/
bitset<_Nb>&
set()
{
this->_M_do_set();
this->_M_do_sanitize();
return *this;
}
/**
* @brief Sets a given bit to a particular value.
* @param pos The index of the bit.
* @param val Either true or false, defaults to true.
* @throw std::out_of_range If @a pos is bigger the size of the %set.
*/
bitset<_Nb>&
set(size_t __pos, bool __val = true)
{
if (__pos >= _Nb)
__throw_out_of_range("bitset -- set() argument too large");
return _Unchecked_set(__pos, __val);
}
/**
* @brief Sets every bit to false.
*/
bitset<_Nb>&
reset()
{
this->_M_do_reset();
return *this;
}
/**
* @brief Sets a given bit to false.
* @param pos The index of the bit.
* @throw std::out_of_range If @a pos is bigger the size of the %set.
*
* Same as writing @c set(pos,false).
*/
bitset<_Nb>&
reset(size_t __pos)
{
if (__pos >= _Nb)
__throw_out_of_range("bitset -- reset() argument too large");
return _Unchecked_reset(__pos);
}
/**
* @brief Toggles every bit to its opposite value.
*/
bitset<_Nb>&
flip()
{
this->_M_do_flip();
this->_M_do_sanitize();
return *this;
}
/**
* @brief Toggles a given bit to its opposite value.
* @param pos The index of the bit.
* @throw std::out_of_range If @a pos is bigger the size of the %set.
*/
bitset<_Nb>&
flip(size_t __pos)
{
if (__pos >= _Nb)
__throw_out_of_range("bitset -- flip() argument too large");
return _Unchecked_flip(__pos);
}
/// See the no-argument flip().
bitset<_Nb>
operator~() const { return bitset<_Nb>(*this).flip(); }
//@{
/**
* @brief Array-indexing support.
* @param pos Index into the %bitset.
* @return A bool for a 'const %bitset'. For non-const bitsets, an
* instance of the reference proxy class.
* @note These operators do no range checking and throw no exceptions,
* as required by DR 11 to the standard.
*
* @if maint
* _GLIBCPP_RESOLVE_LIB_DEFECTS Note that this implementation already
* resolves DR 11 (items 1 and 2), but does not do the range-checking
* required by that DR's resolution. -pme
* The DR has since been changed: range-checking is a precondition
* (users' responsibility), and these functions must not throw. -pme
* @endif
*/
reference
operator[](size_t __pos) { return reference(*this,__pos); }
bool
operator[](size_t __pos) const { return _Unchecked_test(__pos); }
//@}
/**
* @brief Retuns a numerical interpretation of the %bitset.
* @return The integral equivalent of the bits.
* @throw std::overflow_error If there are too many bits to be
* represented in an @c unsigned @c long.
*/
unsigned long
to_ulong() const { return this->_M_do_to_ulong(); }
/**
* @brief Retuns a character interpretation of the %bitset.
* @return The string equivalent of the bits.
*
* Note the ordering of the bits: decreasing character positions
* correspond to increasing bit positions (see the main class notes for
* an example).
*
* Also note that you must specify the string's template parameters
* explicitly. Given a bitset @c bs and a string @s:
* @code
* s = bs.to_string<char,char_traits<char>,allocator<char> >();
* @endcode
*/
template<class _CharT, class _Traits, class _Alloc>
basic_string<_CharT, _Traits, _Alloc>
to_string() const
{
basic_string<_CharT, _Traits, _Alloc> __result;
_M_copy_to_string(__result);
return __result;
}
// Helper functions for string operations.
template<class _CharT, class _Traits, class _Alloc>
void
_M_copy_from_string(const basic_string<_CharT,_Traits,_Alloc>& __s,
size_t, size_t);
template<class _CharT, class _Traits, class _Alloc>
void
_M_copy_to_string(basic_string<_CharT,_Traits,_Alloc>&) const;
/// Returns the number of bits which are set.
size_t
count() const { return this->_M_do_count(); }
/// Returns the total number of bits.
size_t
size() const { return _Nb; }
//@{
/// These comparisons for equality/inequality are, well, @e bitwise.
bool
operator==(const bitset<_Nb>& __rhs) const
{ return this->_M_is_equal(__rhs); }
bool
operator!=(const bitset<_Nb>& __rhs) const
{ return !this->_M_is_equal(__rhs); }
//@}
/**
* @brief Tests the value of a bit.
* @param pos The index of a bit.
* @return The value at @a pos.
* @throw std::out_of_range If @a pos is bigger the size of the %set.
*/
bool
test(size_t __pos) const
{
if (__pos >= _Nb)
__throw_out_of_range("bitset -- test() argument too large");
return _Unchecked_test(__pos);
}
/**
* @brief Tests whether any of the bits are on.
* @return True if at least one bit is set.
*/
bool
any() const { return this->_M_is_any(); }
/**
* @brief Tests whether any of the bits are on.
* @return True if none of the bits are set.
*/
bool
none() const { return !this->_M_is_any(); }
//@{
/// Self-explanatory.
bitset<_Nb>
operator<<(size_t __pos) const
{ return bitset<_Nb>(*this) <<= __pos; }
bitset<_Nb>
operator>>(size_t __pos) const
{ return bitset<_Nb>(*this) >>= __pos; }
//@}
/**
* @brief Finds the index of the first "on" bit.
* @return The index of the first bit set, or size() if not found.
* @ingroup SGIextensions
* @sa _Find_next
*/
size_t
_Find_first() const
{ return this->_M_do_find_first(_Nb); }
/**
* @brief Finds the index of the next "on" bit after prev.
* @return The index of the next bit set, or size() if not found.
* @param prev Where to start searching.
* @ingroup SGIextensions
* @sa _Find_first
*/
size_t
_Find_next(size_t __prev ) const
{ return this->_M_do_find_next(__prev, _Nb); }
};
// Definitions of non-inline member functions.
template<size_t _Nb>
template<class _CharT, class _Traits, class _Alloc>
void
bitset<_Nb>::_M_copy_from_string(const basic_string<_CharT,_Traits,_Alloc>& __s, size_t __pos, size_t __n)
{
reset();
const size_t __nbits = min(_Nb, min(__n, __s.size() - __pos));
for (size_t __i = 0; __i < __nbits; ++__i)
{
switch(__s[__pos + __nbits - __i - 1])
{
case '0':
break;
case '1':
set(__i);
break;
default:
__throw_invalid_argument("bitset -- string contains characters "
"which are neither 0 nor 1");
}
}
}
template<size_t _Nb>
template<class _CharT, class _Traits, class _Alloc>
void
bitset<_Nb>::_M_copy_to_string(basic_string<_CharT, _Traits, _Alloc>& __s) const
{
__s.assign(_Nb, '0');
for (size_t __i = 0; __i < _Nb; ++__i)
if (_Unchecked_test(__i))
__s[_Nb - 1 - __i] = '1';
}
// 23.3.5.3 bitset operations:
//@{
/**
* @brief Global bitwise operations on bitsets.
* @param x A bitset.
* @param y A bitset of the same size as @a x.
* @return A new bitset.
*
* These should be self-explanatory.
*/
template<size_t _Nb>
inline bitset<_Nb>
operator&(const bitset<_Nb>& __x, const bitset<_Nb>& __y)
{
bitset<_Nb> __result(__x);
__result &= __y;
return __result;
}
template<size_t _Nb>
inline bitset<_Nb>
operator|(const bitset<_Nb>& __x, const bitset<_Nb>& __y)
{
bitset<_Nb> __result(__x);
__result |= __y;
return __result;
}
template <size_t _Nb>
inline bitset<_Nb>
operator^(const bitset<_Nb>& __x, const bitset<_Nb>& __y)
{
bitset<_Nb> __result(__x);
__result ^= __y;
return __result;
}
//@}
//@{
/**
* @brief Global I/O operators for bitsets.
*
* Direct I/O between streams and bitsets is supported. Output is
* straightforward. Input will skip whitespace, only accept '0' and '1'
* characters, and will only extract as many digits as the %bitset will
* hold.
*/
template<class _CharT, class _Traits, size_t _Nb>
basic_istream<_CharT, _Traits>&
operator>>(basic_istream<_CharT, _Traits>& __is, bitset<_Nb>& __x)
{
typedef typename _Traits::char_type char_type;
basic_string<_CharT, _Traits> __tmp;
__tmp.reserve(_Nb);
// Skip whitespace
typename basic_istream<_CharT, _Traits>::sentry __sentry(__is);
if (__sentry)
{
basic_streambuf<_CharT, _Traits>* __buf = __is.rdbuf();
for (size_t __i = 0; __i < _Nb; ++__i)
{
static typename _Traits::int_type __eof = _Traits::eof();
typename _Traits::int_type __c1 = __buf->sbumpc();
if (_Traits::eq_int_type(__c1, __eof))
{
__is.setstate(ios_base::eofbit);
break;
}
else
{
char_type __c2 = _Traits::to_char_type(__c1);
char_type __c = __is.narrow(__c2, '*');
if (__c == '0' || __c == '1')
__tmp.push_back(__c);
else if (_Traits::eq_int_type(__buf->sputbackc(__c2),
__eof))
{
__is.setstate(ios_base::failbit);
break;
}
}
}
if (__tmp.empty())
__is.setstate(ios_base::failbit);
else
__x._M_copy_from_string(__tmp, static_cast<size_t>(0), _Nb);
}
return __is;
}
template <class _CharT, class _Traits, size_t _Nb>
basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __os, const bitset<_Nb>& __x)
{
basic_string<_CharT, _Traits> __tmp;
__x._M_copy_to_string(__tmp);
return __os << __tmp;
}
//@}
} // namespace std
#undef _GLIBCPP_BITSET_WORDS
#endif /* _GLIBCPP_BITSET_H */
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