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is_pod Class

Tests if type is POD.

template<class Ty>
    struct is_pod;

Ty

The type to query.

is_pod<Ty>::value is true if the type Ty is Plain Old Data (POD). Otherwise it is false.

Arithmetic types, enumeration types, pointer types, and pointer to member types are POD.

A cv-qualified version of a POD type is itself a POD type.

An array of POD is itself POD.

A struct or union, all of whose non-static data members are POD, is itself POD if it has:

  • No user-declared constructors.

  • No private or protected non-static data members.

  • No base classes.

  • No virtual functions.

  • No non-static data members of reference type.

  • No user-defined copy assignment operator.

  • No user-defined destructor.

Therefore, you can recursively build POD structs and arrays that contain POD structs and arrays.

// std_tr1__type_traits__is_pod.cpp 
// compile with: /EHsc 
#include <type_traits> 
#include <iostream> 
 
struct trivial 
    { 
    int val; 
    }; 
 
struct throws 
    { 
    throws() throw(int) 
        { 
        } 
 
    throws(const throws&) throw(int) 
        { 
        } 
 
    throws& operator=(const throws&) throw(int) 
        { 
        } 
 
    int val; 
    }; 
 
int main() 
    { 
    std::cout << "is_pod<trivial> == " << std::boolalpha 
        << std::is_pod<trivial>::value << std::endl; 
    std::cout << "is_pod<int> == " << std::boolalpha 
        << std::is_pod<int>::value << std::endl; 
    std::cout << "is_pod<throws> == " << std::boolalpha 
        << std::is_pod<throws>::value << std::endl; 
 
    return (0); 
    } 
 
is_pod<trivial> == true
is_pod<int> == true
is_pod<throws> == false

Header: <type_traits>

Namespace: std

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