Namespace
Varianti

std::is_convertible

Da cppreference.com.
< cpp‎ | types

Questa pagina è stata tradotta in modo automatico dalla versione in ineglese della wiki usando Google Translate.

La traduzione potrebbe contenere errori e termini strani. Muovi il puntatore sopra al testo per vedere la versione originale. Puoi aiutarci a correggere gli gli errori. Per ulteriori istruzioni clicca qui.

Click here for the English version of this page

 
C++
 
Utilità libreria
Tipo di supporto (basic types, RTTI, type traits)
Gestione della memoria dinamica
La gestione degli errori
Programma di utilità
Funzioni variadic
Data e ora
Funzione oggetti
initializer_list(C++11)
bitset
hash(C++11)
Gli operatori relazionali
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>=
Coppie e tuple
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.
pair
tuple(C++11)
piecewise_construct_t(C++11)
piecewise_construct(C++11)
Swap, in avanti e spostare
Original:
Swap, forward and move
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
swap
forward(C++11)
move(C++11)
move_if_noexcept(C++11)
declval(C++11)
 
Tipo di supporto
Tipi base
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.
Tipi fondamentali
Larghezza fissa interi tipi (C++11)
Limiti numerici
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 numerico limita interfaccia
Informazioni sul tipo di runtime
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.
Tipo tratti
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.
Categorie di tipo primario
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)
Proprietà del 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)
Operazioni supportate
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_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)
has_virtual_destructor(C++11)
I rapporti e le query di proprietà
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 modifiche
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_cv
remove_const
remove_volatile		(C++11)
(C++11)
(C++11)
add_cv
add_const
add_volatile		(C++11)
(C++11)
(C++11)
make_signed(C++11)
make_unsigned(C++11)
Tipo di trasformazioni
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)
Digitare costanti tratto
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)
 
Elemento definito nell'header <type_traits>
template< class From, class To >
struct is_convertible;
 (dal C++11)
Se un rvalue immaginaria di tipo From può utilizzato nella comunicazione di ritorno di una funzione che restituisce To, cioè, se può essere convertito To utilizzando implicit conversion, fornisce il membro costante value uguale true. In caso contrario, è value false.
Original:
If an imaginary rvalue of type From can used in the return statement of a function returning To, that is, if it can be converted to To using implicit conversion, 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.

Indice

Inherited from std::integral_constant

Member constants

value
[statico]
true se From is convertible to To , false altrimenti
Original:
true if From is convertible to To , false otherwise
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

(pubblico membro statico costante)

Member functions

operator bool
converte l'oggetto in bool, restituisce 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.

(metodo pubblico)

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>

[modifica] Note

Dà risultati ben definiti per i tipi di riferimento, tipi di vuoti, di matrice, e tipi di funzioni.
Original:
Gives well-defined results for reference types, void types, array types, and function types.
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.

[modifica] Esempio

#include <iostream>
#include <type_traits>
 
int main() 
{
    class A {};
    class B: public A {};
    class C {};
 
    bool b2a = std::is_convertible<B*, A*>::value;
    bool a2b = std::is_convertible<A*, B*>::value;
    bool b2c = std::is_convertible<B*, C*>::value;
 
    std::cout << std::boolalpha;
    std::cout << b2a << '\n';
    std::cout << a2b << '\n';
    std::cout << b2c << '\n';
}

Output: 

true
false
false
Estratto da "https://it.cppreference.com/mwiki/index.php?title=cpp/types/is_convertible&oldid=27023"