Namensräume
Varianten

    std::is_convertible

    Aus cppreference.com
    See More

    This page has been machine-translated from the English version of the wiki using Google Translate.

    The translation may contain errors and awkward wording. Hover over text to see the original version. You can help to fix errors and improve the translation. For instructions click here.

    Click here for the English version of this page

    <metanoindex/>

     
    C++
     
    Utilities-Bibliothek
     
    Geben Sie Unterstützung
    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)
    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
    Laufzeit-Typinformationen
    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.
    Exterieur
    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.
    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)
    Unterstützte Operationen
    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)
    Beziehungen und Eigentum Abfragen
    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)
    Typ Modifikationen
    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)
    Typ Transformationen
    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)
    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)
     
    <tbody> </tbody>
    definiert in Header <type_traits>
    template< class From, class To > struct is_convertible;
    		 (seit C++11)
    Wenn eine imaginäre rvalue vom Typ From im Rücklauf Anweisung einer Funktion, die verwendet werden können To, das heißt, wenn sie Verwendung To implicit conversion umgewandelt werden kann, stellt die Elementkonstante value gleich true. Ansonsten value ist 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.

    Inherited from std::integral_constant

    Member constants

    value
    [statisch]
    true wenn From is convertible to To , false anders
    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.

    (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>

    Notes

    Gibt wohldefinierte Ergebnisse für Referenztypen, void-Typen Array-Typen und Funktion Typen .
    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.

    Beispiel

    #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