std::is_same

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Supported operations (C++11)

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is_copy_constructible is_trivially_copy_constructible is_nothrow_copy_constructible

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Type trait constants (C++11)

integral_constant

Defined in header `<type_traits>`

template< class T, class U > struct is_same;		(C++11 feature)

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.

1 Inherited from std::integral_constant

Inherited from std::integral_constant

Member constants


`value`	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>

[edit] Equivalent definition

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

[edit] Example

#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