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is_object Class

Tests if type is an object type.

template<class Ty>
    struct is_object;

Parameters

  • Ty
    The type to query.

Remarks

An instance of the type predicate holds false if the type Ty is a reference type, a function type, or void, or a cv-qualified form of one of them, otherwise holds true.

Example

 

// std_tr1__type_traits__is_object.cpp 
// compile with: /EHsc 
#include <type_traits> 
#include <iostream> 
 
struct trivial 
    { 
    int val; 
    }; 
 
struct functional 
    { 
    int f(); 
    }; 
 
int main() 
    { 
    std::cout << "is_object<trivial> == " << std::boolalpha 
        << std::is_object<trivial>::value << std::endl; 
    std::cout << "is_object<functional> == " << std::boolalpha 
        << std::is_object<functional>::value << std::endl; 
    std::cout << "is_object<trivial&> == " << std::boolalpha 
        << std::is_object<trivial&>::value << std::endl; 
    std::cout << "is_object<float()> == " << std::boolalpha 
        << std::is_object<float()>::value << std::endl; 
    std::cout << "is_object<void> == " << std::boolalpha 
        << std::is_object<void>::value << std::endl; 
 
    return (0); 
    } 
 
is_object<trivial> == true
is_object<functional> == true
is_object<trivial&> == false
is_object<float()> == false
is_object<void> == false

Requirements

Header: <type_traits>

Namespace: std

See Also

Reference

<type_traits>

is_function Class