From cppreference.com
Defined in header
template<classT>structbit_or;(until C++14)template<classT=void>structbit_or;(since C++14)Function object for performing bitwise OR. Effectively calls operator| on type T.
Specializations
The standard library provides a specialization of std::bit_or when T is not specified, which leaves the parameter types and return type to be deduced.
(C++14)
function object implementing x|y deducing parameter and return types
(class template specialization)
(since C++14)Member types
Type Definition result_type(deprecated in C++17)(removed in C++20)Tfirst_argument_type(deprecated in C++17)(removed in C++20)Tsecond_argument_type(deprecated in C++17)(removed in C++20)TThese member types are obtained via publicly inheriting std::binary_function<T,T,T>.
(until C++11)Member functions
operator()
returns the result of bitwise OR of two arguments
(public member function)std::bit_or::operator()
Toperator()(constT&lhs,constT&rhs)const;(constexpr since C++14)Returns the result of bitwise OR of lhs and rhs.
Parameters
lhs, rhs - values to compute bitwise OR of Return value
The result of lhs|rhs.
Exceptions
May throw implementation-defined exceptions.
Possible implementation
constexprToperator()(constT&lhs,constT&rhs)const{returnlhs|rhs;}Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
DR Applied to Behavior as published Correct behavior
C++98 function objects for bitwise operations are missing added