std::logical_or

 

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Defined in header <functional>
template< class T > struct logical_or;		(until C++14)
template< class T = void > struct logical_or;		(since C++14)

Function object for performing logical OR (logical disjunction). Effectively calls operator|| on type T.

Specializations

The standard library provides a specialization of std::logical_or when T is not specified, which leaves the parameter types and return type to be deduced. logical_or<void> (C++14) function object implementing x || y deducing argument and return types (class template specialization)

(since C++14)

Member types

Type	Definition
result_type (deprecated in C++17)(removed in C++20)	bool
first_argument_type (deprecated in C++17)(removed in C++20)	T
second_argument_type (deprecated in C++17)(removed in C++20)	T

These member types are obtained via publicly inheriting std::binary_function<T, T, bool>.

(until C++11)

Member functions

operator()

returns the logical OR of the two arguments (public member function)

std::logical_or::operator()

bool operator()( const T& lhs, const T& rhs ) const;		(until C++14)
constexpr bool operator()( const T& lhs, const T& rhs ) const;		(since C++14)

Returns the logical OR of lhs and rhs.

Parameters

lhs, rhs

-

values to compute logical OR of

Return value

The result of lhs || rhs.

Exceptions

May throw implementation-defined exceptions.

Possible implementation

constexpr bool operator()(const T &lhs, const T &rhs) const { return lhs || rhs; }