Namespaces
Variants
Views
Actions

std::logical_and<void>

From cppreference.com
< cpp‎ | utility‎ | functional
 
 
Utilities library
General utilities
Relational operators (deprecated in C++20)
Integer comparison functions
(C++20)(C++20)(C++20)   
(C++20)
Swap and type operations
(C++14)
(C++11)

(C++11)
(C++11)
(C++17)
Common vocabulary types
(C++11)
(C++17)
(C++17)
(C++17)
(C++11)
(C++17)

Elementary string conversions
(C++17)
(C++17)

Stacktrace
 
Function objects
Function wrappers
(C++11)
(C++11)
Partial function application
(C++20)
(C++11)
Function invocation
(C++17)(C++23)
Identity function object
(C++20)
Reference wrappers
(C++11)(C++11)
Transparent operator wrappers
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
logical_and<>
(C++14)
Negators
(C++17)
Searchers
Constrained comparators
Old binders and adaptors
(until C++17)
(until C++17)
(until C++17)
(until C++17)
(until C++17)(until C++17)(until C++17)(until C++17)
(until C++20)
(until C++20)
(until C++17)(until C++17)
(until C++17)(until C++17)

(until C++17)
(until C++17)(until C++17)(until C++17)(until C++17)
(until C++20)
(until C++20)
 
Defined in header <functional>
template<>
class logical_and<void>;
(since C++14)

std::logical_and<> is a specialization of std::logical_and with parameter and return type deduced.

Contents

[edit] Member types

Member type Definition
is_transparent /* unspecified */

[edit] Member functions

operator()
applies operator&& to lhs and rhs
(public member function)

std::logical_and<>::operator()

template< class T, class U>

constexpr auto operator()( T&& lhs, U&& rhs ) const

  -> decltype(std::forward<T>(lhs) && std::forward<U>(rhs));

Returns the result of lhs && rhs.

Parameters

lhs, rhs - values to AND

Return value

The result of lhs && rhs.

[edit] Notes

The member type is_transparent indicates to the caller that this function object is a transparent function object: it accepts arguments of arbitrary types and uses perfect forwarding, which avoids unnecessary copying and conversion when the function object is used in heterogeneous context, or with rvalue arguments. In particular, template functions such as std::set::find and std::set::lower_bound make use of this member type on their Compare types.

[edit] Example