std::is_reference

 

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Grundtypen 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.
Grundtypen
Feste Breite Integer-Typen(C++11)
ptrdiff_t size_t max_align_t (C++11)	nullptr_t (C++11) offsetof NULL
Numerische Grenzen Original: Numeric limits The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
numeric_limits
C numerische begrenzt Schnittstelle
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type_info type_index (C++11)	bad_typeid bad_cast
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Primären Typ Kategorien Original: Primary type categories The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
is_void (C++11) is_array (C++11) is_pointer (C++11) is_enum (C++11) is_union (C++11) is_class (C++11) is_function (C++11)	is_object (C++11) is_scalar (C++11) is_compound (C++11) is_integral (C++11) is_floating_point (C++11) is_fundamental (C++11) is_arithmetic (C++11)
is_reference (C++11)
is_lvalue_reference (C++11)
is_rvalue_reference (C++11)
is_member_pointer (C++11)
is_member_object_pointer (C++11)
is_member_function_pointer (C++11)

Typ Eigenschaften Original: Type properties The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
is_const (C++11) is_volatile (C++11) is_pod (C++11) is_empty (C++11) is_polymorphic (C++11) is_abstract (C++11)	is_trivial (C++11) is_trivially_copyable (C++11) is_standard_layout (C++11) is_literal_type (C++11) is_signed (C++11) is_unsigned (C++11)

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is_constructible is_trivially_constructible is_nothrow_constructible (C++11) (C++11) (C++11)
is_default_constructible is_trivially_default_constructible is_nothrow_default_constructible (C++11) (C++11) (C++11)
is_copy_constructible is_trivially_copy_constructible is_nothrow_copy_constructible (C++11) (C++11) (C++11)
is_move_constructible is_trivially_move_constructible is_nothrow_move_constructible (C++11) (C++11) (C++11)
is_assignable is_trivially_assignable is_nothrow_assignable (C++11) (C++11) (C++11)
is_copy_assignable is_trivially_copy_assignable is_nothrow_copy_assignable (C++11) (C++11) (C++11)
is_move_assignable is_trivially_move_assignable is_nothrow_move_assignable (C++11) (C++11) (C++11)
is_destructible is_trivially_destructible is_nothrow_destructible (C++11) (C++11) (C++11)
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is_same (C++11) is_base_of (C++11) is_convertible (C++11)	alignment_of (C++11) rank (C++11) extent (C++11)
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aligned_storage (C++11) aligned_union (C++11) decay (C++11) enable_if (C++11)	conditional (C++11) common_type (C++11) underlying_type (C++11) result_of (C++11)
Typ-Trait-Konstanten 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)

 

definiert in Header <type_traits>
template<class T > struct is_reference;		(seit C++11)

Wenn T ein Referenz-Typ (lvalue Verweis oder rvalue Referenz) ist, stellt das Mitglied konstanten value gleich true. Für jede andere Art, value ist false .

Original:

If T is a reference type (lvalue reference or rvalue reference), provides the member constant value equal true. For any other type, value is false.

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Inherited from std::integral_constant

Member constants

value [statisch]	true wenn T is a reference type , false anders Original: true if T is a 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. (public static Mitglied konstanten)

Member functions

operator bool	wandelt das Objekt bool, gibt 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. (öffentliche Elementfunktion)

Member types

Type 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>

Mögliche Implementierung

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

Beispiel

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

Output:

false true true false true true

Siehe auch

is_lvalue_reference (C++11)	prüft, ob ein Typ ist lvalue Verweis Original: checks if a type is lvalue reference The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (Klassen-Template)
is_rvalue_reference (C++11)	prüft, ob ein Typ ist rvalue Verweis 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. (Klassen-Template)