std::logical_and

 

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

Function object for performing logical AND (logical conjunction). Effectively calls operator&& on type T.

Specializations

The standard library provides a specialization of std::logical_and when T is not specified, which leaves the parameter types and return type to be deduced. logical_and<void> 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) bool first_argument_type(deprecated in C++17) T second_argument_type(deprecated in C++17) T

(until C++20)

Member functions

operator()

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

std::logical_and::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 AND of lhs and rhs.

Parameters

lhs, rhs

-

values to compute logical AND of

Return value

The result of lhs && rhs.

Exceptions

(none)

Possible implementation

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