std::is_base_of

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Os operadores relacionais Original: Relational operators The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

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

Pares e tuplas Original: Pairs and tuples 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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Apoio a tipos

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.
Tipos fundamentais
Tipos inteiros de largura fixos (C++11)
ptrdiff_t size_t max_align_t (C++11)	nullptr_t (C++11) offsetof NULL
Limites numéricos 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 numérico limita interface
Informações de tipo de tempo de execução Original: Runtime type information The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
type_info type_index (C++11)	bad_typeid bad_cast
Características de tipo Original: Type traits The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
Principais categorias de tipo 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)
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is_rvalue_reference (C++11)
is_member_pointer (C++11)
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Propriedades de tipo 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)

Operações apoiadas Original: Supported operations The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
is_constructibleis_trivially_constructibleis_nothrow_constructible (C++11)(C++11)(C++11)
is_default_constructibleis_trivially_default_constructibleis_nothrow_default_constructible (C++11)(C++11)(C++11)
is_copy_constructibleis_trivially_copy_constructibleis_nothrow_copy_constructible (C++11)(C++11)(C++11)
is_move_constructibleis_trivially_move_constructibleis_nothrow_move_constructible (C++11)(C++11)(C++11)
is_assignableis_trivially_assignableis_nothrow_assignable (C++11)(C++11)(C++11)
is_copy_assignableis_trivially_copy_assignableis_nothrow_copy_assignable (C++11)(C++11)(C++11)
is_move_assignableis_trivially_move_assignableis_nothrow_move_assignable (C++11)(C++11)(C++11)
is_destructibleis_trivially_destructibleis_nothrow_destructible (C++11)(C++11)(C++11)
has_virtual_destructor (C++11)
Relacionamentos e consultas de propriedade Original: Relationships and property queries The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
is_same (C++11) is_base_of (C++11) is_convertible (C++11)	alignment_of (C++11) rank (C++11) extent (C++11)
Tipo modificações Original: Type modifications The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
remove_cvremove_constremove_volatile (C++11)(C++11)(C++11) add_cvadd_constadd_volatile (C++11)(C++11)(C++11) make_signed (C++11) make_unsigned (C++11)	remove_reference (C++11) add_lvalue_referenceadd_rvalue_reference (C++11)(C++11) remove_pointer (C++11) add_pointer (C++11) remove_extent (C++11) remove_all_extents (C++11)
Transformações tipo Original: Type transformations The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.
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)
Digite constantes traço 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)

 

<tbody> </tbody>

Definido no cabeçalho <type_traits>
template< class B, class D > struct is_base_of;		(desde C++11)

Se D é derivado B ou se ambos são a classe de não-união mesmo, proporciona o membro value constante igual a true. Caso contrário value é false.

Original:

If D is derived from B or if both are the same non-union class, provides the member constant value equal to true. Otherwise value is false.

The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

Herdado de std::integral_constant

Member constants

value [estática]	true se D is derived from B , false contrário Original: true if D is derived from B , false otherwise The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (membro estático público constante)

Member functions

operator bool	converte o objeto em bool, retorna 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. (função pública membro)

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>

Exemplo

#include <iostream>
#include <type_traits>

class A {};

class B : A {};

class C {};

int main() 
{
    std::cout << std::boolalpha;
    std::cout << "a2b: " << std::is_base_of<A, B>::value << '\n';
    std::cout << "b2a: " << std::is_base_of<B, A>::value << '\n';
    std::cout << "c2b: " << std::is_base_of<C, B>::value << '\n';
}

Saída:

a2b: true
b2a: false
c2b: false