std::is_same

 

C++

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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)

Supported operations
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)
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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)
Type trait constants
integral_constant (C++11)

 

Defined in header <type_traits>
template< class T, class U > struct is_same;		(since C++11)

If T and U name the same type with the same const-volatile qualifications, provides the member constant value equal to true. Otherwise value is false.

Inherited from std::integral_constant

Member constants

value [static]	true if T and U is the same type , 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>

Possible implementation

template<class T, class U> struct is_same : std::false_type {};   template<class T> struct is_same<T, T> : std::true_type {};

Example

run this code

#include <iostream>
#include <type_traits>
#include <cstdint>
 
int main()
{
    std::cout << std::boolalpha;
    std::cout << std::is_same<int, int32_t>::value << '\n';
    std::cout << std::is_same<int, int64_t>::value << '\n';
    std::cout << std::is_same<float, int32_t>::value << '\n';
}

Output:

true
false
false