std::is_lvalue_reference

 

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rel_ops::operator!= rel_ops::operator> rel_ops::operator<= rel_ops::operator>=

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Tipos básicos Original: Basic types The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
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is_lvalue_reference (C++11)
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Escriba constantes rasgos Original: Type trait constants The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
integral_constant (C++11)

 

Defined in header <type_traits>
template< class T > struct is_lvalue_reference;		(ya que C + +11)

Si T es un tipo de referencia lvalue, establece en el miembro constante value true iguales. Para cualquier otro tipo, es value false .

Original:

If T is an lvalue reference type, provides the member constant value equal true. For any other type, value is false.

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You can help to correct and verify the translation. Click here for instructions.

Inherited from std::integral_constant

Member constants

value [estático]	true si T is an lvalue reference type , false lo contrario Original: true if T is an lvalue reference type , false otherwise The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (público miembro constante estática)

Member functions

operator bool	convierte el objeto a bool, devuelve value Original: converts the object to bool, returns value The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (miembro público función)

Member types

Tipo Original: Type The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.	Definition
value_type	bool
type	std::integral_constant<bool, value>

Posible implementación

template<class T> struct is_lvalue_reference : std::false_type {}; template<class T> struct is_lvalue_reference<T&> : std::true_type {};

Ejemplo

#include <iostream>
#include <type_traits>
 
class A {};
 
int main() 
{
    std::cout << std::boolalpha;
    std::cout << std::is_lvalue_reference<A>::value << '\n';
    std::cout << std::is_lvalue_reference<A&>::value << '\n';
    std::cout << std::is_lvalue_reference<A&&>::value << '\n';
    std::cout << std::is_lvalue_reference<int>::value << '\n';
    std::cout << std::is_lvalue_reference<int&>::value << '\n';
    std::cout << std::is_lvalue_reference<int&&>::value << '\n';
}

Output:

false
true
false
false
true
false

Ver también

is_reference (C++11)	Comprueba si un tipo está bien lvalue referencia o referencia rvalue Original: checks if a type is either lvalue reference or rvalue reference The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (clase de plantilla)
is_rvalue_reference (C++11)	comprueba si un tipo es' rvalue referencia Original: checks if a type is rvalue reference The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (clase de plantilla)