std::bitset<N>::set
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bitset& set();
(1)
(noexcept since C++11) (constexpr since C++23)
bitset& set( std::size_t pos, bool value = true );
(2)
(constexpr since C++23)
Sets all bits to true or sets one bit to specified value.
1) Sets all bits to true.
2) Sets the bit at position pos to the value value.
[edit] Parameters
pos
-
the position (counting from 0, i.e. from least significant to most significant) of the bit to set
value
-
the value to set the bit to
[edit] Return value
*this
[edit] Exceptions
[edit] Example
Run this code
#include <bitset> #include <cstddef> #include <iostream> int main() { std::bitset <8> b; std::cout << b << '\n'; std::cout << b.set() << '\n'; std::cout << b.reset() << '\n'; for (std::size_t i = 1; i < b.size(); i += 2) b.set(i); std::cout << b << '\n'; }
Output:
00000000 11111111 00000000 10101010
[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 186 | C++98 | the type of value was int | corrected to bool |
| LWG 2250 | C++98 | the behavior was undefined if pos does not correspond to a valid bit position |
always throws an exception in this case |