std::is_convertible

 

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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)
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integral_constant (C++11)

 

Defined in header <type_traits>
template< class From, class To > struct is_convertible;		(since C++11)

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.

Inherited from std::integral_constant

Member constants

value [static]	true if From is convertible to To , false otherwise (public static member constant)

Member functions

operator bool	converts the object to bool, returns value (public member function)

Member types

Type	Definition
value_type	bool
type	std::integral_constant<bool, value>

Notes

Gives well-defined results for reference types, void types, array types, and function types.

Example

#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