C++

Reference

<functional>

class template
<functional>

std::bit_or

template <class T> struct bit_or;
Bitwise OR function object class
Binary function object class whose call returns the result of applying the bitwise "or" operation between its two arguments (as returned by operator |).

Generically, function objects are instances of a class with member function operator() defined. This member function allows the object to be used with the same syntax as a function call.

It is defined with the same behavior as:

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template <class T> struct bit_or {
  T operator() (const T& x, const T& y) const {return x|y;}
  typedef T first_argument_type;
  typedef T second_argument_type;
  typedef T result_type;
};

Objects of this class can be used on standard algorithms such as transform or accumulate.

Template parameters

T
Type of the arguments and return type of the functional call.
The type shall support the operation (operator|).

Member types

member typedefinitionnotes
first_argument_typeTType of the first argument in member operator()
second_argument_typeTType of the second argument in member operator()
result_typeTType returned by member operator()

Member functions

T operator() (const T& x, const T& y)
Member function returning the bitwise "or" of its arguments (x|y).

Example

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// bit_or example
#include <iostream>     // std::cout
#include <functional>   // std::bit_or
#include <numeric>      // std::accumulate
#include <iterator>     // std::end

int main () {
  int flags[] = {1,2,4,8,16,32,64,128};
  int acc = std::accumulate (flags, std::end(flags), 0, std::bit_or<int>());
  std::cout << "accumulated: " << acc << '\n';
  return 0;
}

Output:

accumulated: 255


See also

bit_and
Bitwise AND function object class (class template)
bit_xor
Bitwise XOR function object class (class template)