is_pod template in C++

The std::is_pod template of C++ STL is used to check whether the type is a plain-old data(POD) type or not. It returns a boolean value showing the same.

Syntax:

template < class T > struct is_pod;

Parameter: This template contains single parameter T (Trait class) to check whether T is a pod type or not.

Return Value: This template returns a boolean value as shown below:

• True: if the type is a pod type.
• False: if the type is a non-pod type.

Below programs illustrate the std::is_pod template in C++ STL:

Program 1:

// C++ program to illustrate
// std::is_pod template

#include <iostream>
#include <type_traits>
using namespace std;

struct gfg {
    int var1;
};

struct sam {
    int var2;

private:
    int var3;
};

struct raj {
    virtual void func();
};

int main()
{
    cout << boolalpha;
    cout << "is_pod:" << '\n';
    cout << "gfg:" << is_pod<gfg>::value << '\n';
    cout << "sam:" << is_pod<sam>::value << '\n';
    cout << "raj:" << is_pod<raj>::value << '\n';
    return 0;
}

Output:

is_pod:
gfg:true
sam:false
raj:false

Program 2:

// C++ program to illustrate
// std::is_pod template

#include <iostream>
#include <type_traits>
using namespace std;

class gfg {
    int var1;
};

class sam {
    int var2;

private:
    int var3;
};

class raj {
    virtual void func();
};

int main()
{
    cout << boolalpha;
    cout << "is_pod:" << '\n';
    cout << "gfg:" << is_pod<gfg>::value << '\n';
    cout << "sam:" << is_pod<sam>::value << '\n';
    cout << "raj:" << is_pod<raj>::value << '\n';
    return 0;
}

Output:

is_pod:
gfg:true
sam:true
raj:false

Program 3:

// C++ program to illustrate
// std::is_pod template

#include <iostream>
#include <type_traits>
using namespace std;

union gfg {
    int var1;
};

union sam {
    int var2;

private:
    int var3;
};

int main()
{
    cout << boolalpha;
    cout << "is_pod:" << '\n';
    cout << "gfg:" << is_pod<gfg>::value << '\n';
    cout << "sam:" << is_pod<sam>::value << '\n';
    return 0;
}

Output:

is_pod:
gfg:true
sam:false