Namespaces
Variants
Actions

std::bitset<N>::to_string

From cppreference.com
< cpp‎ | utility‎ | bitset
 
 
Utilities library
Language support
Type support (basic types, RTTI)
Library feature-test macros (C++20)
Program utilities
Variadic functions
Coroutine support (C++20)
Contract support (C++26)
Three-way comparison
(C++20)
(C++20)
(C++20)(C++20)(C++20)  
(C++20)(C++20)(C++20)

General utilities
Relational operators (deprecated in C++20)
Integer comparison functions
(C++20)(C++20)(C++20)  
(C++20)
Swap and type operations
(C++20)
(C++14)
(C++11)
(C++11)
(C++23)
(C++11)
(C++17)
Common vocabulary types
(C++11)
(C++17)
(C++17)
(C++17)
(C++11)
(C++17)
(C++23)


 
(1)
template< class CharT, class Traits, class Allocator >

std::basic_string <CharT, Traits, Allocator>
    to_string( CharT zero = CharT('0'),

               CharT one = CharT('1') ) const;
(until C++11)
template<

    class CharT = char,
    class Traits = std::char_traits <CharT>,
    class Allocator = std::allocator <CharT>
>
std::basic_string <CharT, Traits, Allocator>
    to_string( CharT zero = CharT('0'),

               CharT one = CharT('1') ) const;
(since C++11)
(constexpr since C++23)
template< class CharT, class Traits >

std::basic_string <CharT, Traits>
    to_string( CharT zero = CharT('0'),

               CharT one = CharT('1') ) const;
(2) (until C++11)
template< class CharT >

std::basic_string <CharT> to_string( CharT zero = CharT('0'),

                                    CharT one = CharT('1') ) const;
(3) (until C++11)
std::string to_string( char zero = '0', char one = '1' ) const;
(4) (until C++11)

Converts the contents of the bitset to a string. Uses zero to represent bits with value of false and one to represent bits with value of true.

The resulting string contains N characters with the first character corresponds to the last (N-1th) bit and the last character corresponding to the first bit.

All template type arguments need to be provided because function templates cannot have default template arguments. Overloads (2-4) are provided to simplify the invocations of to_string:

2) Uses the default allocator std::allocator .
3) Uses the default character trait std::char_traits and the default allocator std::allocator .
4) Uses the default character type char, the default character trait std::char_traits and the default allocator std::allocator .
(until C++11)

Contents

[edit] Parameters

zero - character to use to represent false
one - character to use to represent true

[edit] Return value

1) The converted string.
2) to_string<CharT, Traits, std::allocator <CharT>>(zero, one).
3) to_string<CharT, std::char_traits <CharT>, std::allocator <CharT>>(zero, one).
4) to_string<char, std::char_traits <char>, std::allocator <char>>(zero, one).

[edit] Exceptions

May throw std::bad_alloc from the std::basic_string constructor.

[edit] Notes

Since C++11, functions templates can have default template arguments. LWG issue 1113 removed the helper overloads (2-4) and added the corresponding default template arguments in (1).

[edit] Example

Run this code
#include <bitset>
#include <iostream>
 
int main()
{
 std::bitset <8> b{42};
 std::cout << b.to_string() << '\n'
 << b.to_string('*') << '\n'
 << b.to_string('O', 'X') << '\n';
}

Output: 

00101010
**1*1*1*
OOXOXOXO

[edit] Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 396 C++98 zero and one bits were converted to characters ​0​
and 1 (which do not correspond to '0' and '1') 		added parameters to provide
values for these characters
LWG 434 C++98 all template arguments needed to be provided added overloads (2-4)
LWG 853 C++98 overloads (2-4) did not have the default
arguments added by LWG issue 396 		also added

[edit] See also

returns an unsigned long integer representation of the data
(public member function) [edit]
(C++11)
returns an unsigned long long integer representation of the data
(public member function) [edit]

AltStyle によって変換されたページ (->オリジナル) /